It smells nutty, almost vanilla-like, buttery, and just generally delicious: brown (or burnt) butter. It requires only one ingredient and just a little bit of patience. That simple process unleashes a series of chemical reactions which all contribute to the amazing flavor and smell of brown butter. It’s pure chemistry.
But what do you then do with that brown butter? Eating it as is, isn’t the best experience. Here, we’ll be using it to make delicious cookies. Combining chemistry + great tasting food is the best, isn’t it?
What is brown butter?
Brown butter is a very good description of what it is: butter that has been browned. That doesn’t mean all the butter will have actually turned brown. Instead, the majority of the butter is still yellowish, but, at the bottom, you’ll find browned pieces. The brown butter hasn’t just changed color, the smell is also noticeably different from that of regular butter. It smells nutty, caramel, maybe vanilla-like. The flavor profile is actually quite complex!
We’ve written about brown butter extensively. Want to know exactly what happens when making it? Do a deep dive on brown butter.
Brown butter vs. Butter = Missing water
Aside from the aromas that are formed when making brown butter, another crucial change takes place: water evaporates.
Butter isn’t a pure fat like olive oil or soybean oil are. Instead, butter is an emulsion of water in fat. Water droplets are dispersed throughout the fat. It gives butter a unique role in foods like cookies, it doesn’t just add fat, but also moisture. However, when browning butter, all that water will evaporate. It’s why you also end up with significantly less brown butter than what you started out with in butter weight.
When browning butter you lose about 15-20% of the initial weight. This is due to water evaporating.
Why use brown butter in cookies?
Just about all cookies will contain some sort of fat. Fat is important for flavor, but also texture and mouthfeel. A cookie without fat would be more like a cracker than a cookie. Fat also helps achieve a good cookie dough consistency and helps ensure the cookie doesn’t turn dry.
Fats and oils are all made up of the same type of molecules: triglycerides. Sunflower oil, olive oil, butter fat, lard, they are all a mix of triglycerides. They differ in the exact types of triglycerides, which is why some fats are liquid are room temperature whereas others are solid. Fats that are liquid at room temperature are generally called oils. They can be used in cookies, but tend to make quite an unstable dough. The oil can easily leach out of the dough, giving an unappetizing cookie. It’s why a lot of cookies often contain at least some fats that are solid at room temperature.
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Brown butter can be used in these instances. But it’s just one reason for using it.
A lot of the more refined oils, such as soybean or safflower oil have been refined quite extensively. During this process, a lot of the minor molecules are taken out. This helps to preserve the oils so they don’t oxidize and develop off-flavors. However, it also means these oils are pretty bland. They don’t really taste like anything specific.
Enter: brown butter. Brown butter is possibly the opposite of being refined. It is full of ‘contaminants’ that will likely decrease the shelf life (best to use it within a couple of days after making if you’re not taking any steps to prevent it from oxidizing). But, these are full of flavor. So, when using brown butter in a cookie recipe, you’ll add a ton of depth of flavor to make your cookies pop.
How to use brown butter in cookies?
Since brown butter still contains the same fats that the butter you started out with contains, it will behave in a very similar manner. The only tweak you should make to your recipes is to account for the loss of moisture. As such, if you’re replacing 100g of regular butter, you should replace it with 85g of brown butter and 15g of water. This should give a cookie dough that’s very similar to one using just butter, but with more flavor (and a brown color!).
- 75 butter
- 100g sliced almonds (can be either with or without the brown skin on, we used with skin on)
- 100g granulated (regular) sugar
- 60g all purpose flour
- 135g egg white (from 3-4 eggs)
Making brown butter
- Weigh the butter and place it in a small sauce pan. Place the pan over low/medium heat.
- The butter will melt initiall. You can swirl the pan or use a spatula to move the butter around to speed up the melting. After this is it easiest not to touch the pan at all, there is no need really to stir. If the butter start sputtering, turn down the heat.
- Once the butter is melted you will want it to boil gently. During this process the remaining moisture in the butter evaporates. Once the moisture has evaporated the butter might not look as warm anymore, but actually this is the point things start moving quickly! You will notice that on the bottum of the pan particles start to form which will turn brown (and if heated too quickly black!). Continue to heat until they are a dark brown. The butter will smell very nutty and be full of flavour! Turn off the heat once the butter has browned. If you accidentally burn it just slightly, don't worry, it adds a bit of extra flavour!
- Pour the butter through a fine mesh (or cheese cloth) to sieve out the dark particles and leave the butter to cool down to the touch so it doesn't cook your eggs in the next step.
Making the cookies
- Mix the sliced almonds, sugar and flour in a bowl. (Pre-mixing helps prevent clumps of flour from forming in your batter in the next step since the flour particles are surrounded by sugar.)
- Fold the butter through the mixture.
- Add in the egg whites (no yolks!*). The mixture will not be smooth and quite lumpy with all the almonds, that is ok.
- Add little spoonfuls of batter on a baking tray covered with parchment paper or silicone mats. Ensure that the cookie batter is spread out completely flat, you don't want any almonds lying on top of one another. The cookie will not spread during baking, so the size you spread it out here will be the final seize. They'll be only 1-3mm thick!
- Bake the cookies in a pre-heated oven at 180°C (350°F) for about 15-18 minutes. Watch the tuiled like a hawk towards the end, once they start turning brown, they are prone to burning. You don't want to burn the cookies here, instead, making them a medium brown colour (like bread). Every oven will behave slightly different.
- The cookies are flexible when just out of the oven, so you can curl them up. If you don't want to curl them, keep them flat on the tray for a few minutes so they remain straight. Once they're firm, remove the cookies to a cooling rack or plate to cool further.
*Use the yolks for making ice cream!
Dufossé, Laurent & Latrasse, A. & Spinnler, Henry-Eric. (1994). Importance of Lactones in Food Flavors – Structure, Distribution, Sensory Properties and Biosynthesis. Sciences Des Aliments. 14. 17-50. link
Patrick Fox, Advanced Dairy Chemistry volume 3: Lactose, water, salts and vitamins, 2nd edition, p.420, link
Gerda Urbach, Butter flavour in food systems, Food Research Quarterly Volume 51, 1991, link