Every chef I know has given some thought to what they would want their secret ingredient to be if they were ever on Iron Chef. For me, the answer will always be butter. This is not because I am a Paula Dean doppelgänger that would love nothing more than to eat butter straight from the packaging. I simply love the delicate flavors and textures that one can achieve with butter. Such a simple ingredient with so many uses. But, more than anything, it is because I love the smell of brown butter. I really think the French, “beurre noisette”, captures all the sexy nuances of brown butter. The nutty aroma. The caramelly toasted milk flavors. The scattered brown specks hinting at all the depth of flavor of vanilla bean. Say it with me – noisette. We’ll be exploring butter from how to make it at home to clarifying to browning. And, in preparation for a visit from St. Nick, we’ll leave you with a recipe for brown butter shortbread cookies that will have Santa leaving you a little extra loot this year.
Making butter is simple. I have done it on accidentally on several occasions in wayward attempts at whipping cream. Anyone growing up on a farm pre-1950’s might know this process as churning butter. Whether wailing away at the old butter churn or letting your mixer do all the work, the same process is occurring. What is that process?
The first step is to figure out how much butter we want. As a general rule, we will produce a little less than half the volume of butter as the cream with which we started. Keep in mind that is volume not weight. The fats and liquids that we are separating have different densities. Therefore, the same volumes will have different weights. The second step is to make sure we are using the right kind of cream. We want to use “heavy” cream for our butter making, because it contains the highest quantity of fat, typically 30% or more. Avoid “whipping” cream. “Whipping” cream often denotes a product that has chemical stabilizers added, which will be counterproductive to our butter making. The last step is to pour the cream in the bowl of your mixer and let it whip1.
As the cream whips, air will be incorporated into the viscous liquid. Fat globules attach to the outside of the air bubbles lending them structure, which, in turn, allows for more air to join the fun. If we stopped there, we’d have whipped cream. Instead, we are going to keep the mixer running. We will eventually hit a point at which the fat globules coating the air bubbles are pressed together by the air bubbles. The fat globules will then come together into a larger mass. This process works best at temperatures around 60F, where the fats are in a semi-liquid state. As we continue to whip the cream, the groupings of fat globules will grow larger until we start having visible chunks of fat coming together. From there, the separating process will continue. The fats will bunch together and squeeze a large portion of the liquids out of their structure. Once the butter pieces have coalesced into a few large chunks, it is time to scoop out our butter and store it.
Press the butter pieces together to form one solid ball. At this point our butter is roughly 80% milk fat, 18% water trapped in the fat, and 2% milk solids (proteins and salts) carried in the water. This is also the make up of most American butters. Some more expensive European butters we see in stores, such as Plugrá, have a lower water content (typically about 10%) and higher fat content. While this is better for making clarified butter where we only want the fats, it is not good in all applications. When we lose water we also lose milk solids, which create most of the flavor in butter and are crucial for browning. If you do want to lower the water content of your homemade butter, run cold water over it. Since water bonds with water, it will actually pull water out of the butter, reducing the water content. Otherwise, place your butter in a convenient crock and store it in your fridge.
Now, what is that liquid that’s still hanging out in the standmixer? Its buttermilk, of course. Do not confuse our homemade buttermilk with the buttermilk on store shelves. That buttermilk has cultures added to it much like yogurt. What we have is, quite literally, milk from butter. Buttermilk produced from the old-fashion churning method did tend to sour from airborne bacteria that would culture the milk during the churning process. With the use of machines that make butter in more sterile environments at less bacteria-conducive temperatures, buttermilk is no longer cultured through wild bacteria. What we have is in the bowl more akin to reduced fat milk (about 1- 2% fat). I suggest saving this to drink with your cookies.
Having done all this work to make a beautiful, uniform crock of butter, let’s take it apart. In essence, this is what clarifying does. Butter is what we call a strong emulsion, meaning that it has fats and water combined in a solution that does not separate – at least while it is solid. When we heat up the butter, however, the fats convert into a liquid state and no longer have the structure to hold the water. Try this over low heat in a heat-proof, glass measuring cup (I cannot emphasize enough the importance of heat-proof glass here). You will notice that, once the butter is completely melted, it will quickly separate, much like oil (a fat) and vinegar (a water-based, acidic solution). Water is more dense than fat. So, the water will collect at the bottom, with the milk fats above. There is also a milky substance floating on top of the fat, as well as a milky quality to the water. This is…well…the milk. We are seeing that 2% content of milk solids trapped in the butter. Most of it will stay with the water (casein and salts), but some will detach and float to the top (whey proteins). This is the entire purpose behind clarifying butter (i.e. getting rid of the milkiness).
The milk solids are what limit our cooking abilities with butter. Unclarified butter’s smoking point, the point at which it starts to burn, is around 300F. This low smoking point is due to the milk solids, which are what start burning first. If we remove those milk solids, we can increase the smoking point to be comparable to vegetable oils and lard, about 400F. At those temperatures, we can use butter for high-heat cooking techniques like sautéing and meat browning.
Once we have the butter melted and have allowed it to separate, all we have to do is skim the whey film from the top of the fats and pour the fats off the water. The clarified butter can then be stored in the back of the fridge and used as needed. For a little extra flavor in our clarified butter, we can make “ghee”, an Indian version of clarified butter in which the butter is browned slightly before separating the fats.
And that segues nicely into brown butter.
Now, for the reason that I believe butter was invented: brown butter.
Brown butter is butter that we heat hot enough to allow the milk solids to toast, but stop before they burn. Browning butter is one of those techniques for which every chef seems to have their own little trick. I’ve heard everything from adding a tablespoon of cold cream to stop the cooking process to dipping the bottom of the pan in cold water to knowing when to stop cooking by the size of the bubbles. Since this is my post, I have the chance to poo-poo all these other methods and tout my own as superior to all others. Ready for it?
Listen. Not to me, to the butter (you should also probably continue to listen to me). We are going to listen for when it is done.
We’ve got our butter in the pan. Being the smart cooks that we are, we have kept in mind that our butter will start toasting at around 250F, 38 degrees past the boiling point of water (212F). This means that by the time we have browned the butter, we will have also cooked out the 18% water content of our butter. So, we need to start with more butter than our desired end amount of browned butter:
where b is the initial amount of butter and b’ is the desired amount of brown butter.
The pan goes onto medium heat and then we wait. The butter will melt in the pan. As we approach 212F, the water will begin to boil and evaporate away. The boiling process will create a white foam on top of the fat. This is the milk proteins coagulating and briefly trapping the escaping steam.
Once we pass 212F, we’ll start to hear a sizzling sound. That “sizzle” is a combination of water hissing into vapor and flavorful proteins and salts frying in the fat. We are listening for the dying away of the sizzle. Our pan of butter will hit a crescendo, if you will, of bubbling fatty brown goodness, then start to die away. As soon as we notice the sound of the sizzle lessening, we are going to pull the pan from the heat (click here to hear an MP3 of the change in sizzle, at the 10s mark). The butter will just have started to brown at this point. Because there is carry over cooking in the hot pan and the hot fat, the butters will continue to brown for a bit, but away from the heat, we will never hit the 300F smoking point. However, if you wait for the sizzle to completely fade, the pan will be hot enough that the milk solids will continue cooking, passing the realm of tasty deliciousness and entering the forbidden kingdom of burnt nasty bits.
With our butter perfectly browned, we can either pour off the now brown butter flavored fats for our own homemade ghee2 or let the brown butter set at room temperature until solid before refrigerating. Be sure to stir up the butter to distribute the toasted milk solids throughout the fat before chilling3.
At this point, we have made our own homemade butter, clarified some of it for miscellaneous cooking, and browned a portion of it for the shear sake of tastiness. Well let’s put that tastiness to good use and make some cookies.
Ever wonder where shortbread got its name? Or shortcake for that matter? Or shortening? If you guessed science…well, tell them what they won, Rod.
The “short” in all of those terms comes for the shortening of the gluten strands in the flour. For more on glutens, check out my incredibly interesting post on the science of bread-making4. Fats of all kinds block the entanglement of gluten proteins, preventing the formation of long strands. Shorter strands of gluten provide far less structure to baked goods, creating a crumbly texture. The more we work the fats into the flour the more they interfere with gluten development and the crumblier the final product.
The process for making these cookies is pretty simple. We are simply going to combine some room temperature brown butter with sugar and beat them together until just combined. We don’t want to work in too much air. Air not only creates the majority of the rise we see in cookies, but tenderizes. Unlike most cookies these shortbreads don’t need any rise and will already be plenty tender. We then add in the vanilla, flour, and salt, and mix until the lot comes together in a uniform dough. That’s it! Its that easy.
We can then roll the dough out to about 1/2-inch thickness (dust the dough with sugar, not flour, to get an embedded sugar crust) and cut into 2×3-inch rectangles. Place the rectangles on a sheetpan and stick them in the freezer to chill. Just like in pie crust5, we are better off with cold butter. Here, we want solid butter to maintain the shape of the cookie and to prevent spread, rather than for flakiness. You can leave the uncooked cookies in the freezer for up to 6 months before baking them. They will go straight from the freezer into the oven.
Once they have made a stop over in your 350F oven for about 25 minutes, they are mantle ready and set for Santa consumption. Happy eating and welcome to the “Nice” list.
1. Great little chef tip: Wrap a sheet of plastic wrap around the mixer to cover the gap above the bowl. This will prevent stray drop of cream from splattering everywhere, especially as the solid butter forms and starts tumbling through the liquids.
2. All of the milk solids will sink to the bottom and there will be no water to worry about
3. I will generally save the toasty milk solids from making ghee to use in brown butter ice cream or something of the sort.
4. For the record, I am totally unabashed by the blatant internal self-promotion.
5. I’m telling you, no shame at all.