While traveling and meeting you on my book tour these past few months, I’ve learned two things. (1) You cannot take a jar of peanut butter through security. They will confiscate it. And (2) many of you—not only in person but also in comments, emails, social media, etc.—have told me that you LOVE learning about the science, background, whys, and why nots in baking. Why some ingredients work, why others do not. The particular methods for particular recipes and why they are used. I’m fascinated by it all too! So that’s why I’m focusing on a few new topics in this baking basics series, including today’s crucial rule. I’m the most impatient person on this planet, but something I always treat with patience is baking. You can’t rush baking. You can’t speed up cookie dough chilling, the chocolate setting, or the cheesecake evenly firming. You can’t rush French macarons or skip a dough proofing step. And you absolutely can’t ignore the need for room temperature ingredients by using straight-from-the-fridge instead. Certain recipes call for ingredients like eggs, yogurt, cream cheese, butter, and/or milk to be at room temperature but many people ignore this step. No! Don’t! Room temperature isn’t listed next to ingredients for fun. There’s science and legitimate reason behind the importance of temperature. Which brings me to my #2 tip in my 10 best baking tips: if a recipe calls for room temperature ingredients, use room temperature ingredients. There is no way around this and if you use, say, cold butter or cold eggs when they should be room temperature—your recipe won’t live up to its potential. And it most certainly won’t taste the way it should.

Why Is Room Temperature Important?

When at room temperature, eggs, butter, and other dairy ingredients form an emulsion which traps air. While baking in the oven, that trapped air expands and produces a fluffy baked good. For example: a light-textured confetti cake or tender strawberry cupcakes. Not only this, room temperature ingredients bond together very easily since they’re warmer, creating a seamless and evenly textured batter. A smooth batter = a uniformly textured baked good. Cold ingredients do not incorporate together as easily. Or even at all! This results in clumpy frosting, chunky cheesecake, dense cookies, flat breads and muffins, etc. In other words, complete recipe failures.

Room Temperature Butter

A lot of recipes start with room temperature butter creamed with sugar. Creaming just means that the two are beaten together until light, white, and creamy. When you think about it, sugar is nothing but a billion little jagged-edged (and delicious!) crystals. When beaten with butter, their edges dig out little air pockets in the butter. If your butter is too cold because you just took it out of the fridge or only gave it 10 minutes to soften, the sugar crystals can’t claw their way through the hard butter. No trapped air, no light and airy baked good. If the butter is at its magic room temperature, the sugar effectively aerates the butter during that creaming process. The baking powder and/or soda helps expand those little air pockets the creaming process created and your finished baked good is light! Tender! Fluffy! Just as it should be because you followed the rules with the MAGIC that is room temperature butter. And the same goes for room temperature butter in buttercream frostings. How can you start a beautifully creamy and fluffy frosting with cold butter? And the same for cream cheese frosting—with cold cream cheese? You can’t! The resulting frosting will be clumpy. It’s not pretty and chunks of butter or cream cheese in your frosting certainly isn’t appetizing. When butter is at room temperature, you should be able to press your finger into it and make an indent easily, without your finger sliding anywhere. Firm, but not cold. Lightly softened without being greasy or melty in the slightest. Here’s a photo: How to bring butter to room temperature: no rocket science here! Simply take the butter out of the refrigerator 1 hour before beginning your recipe. No ifs, ands, or buts. Sometimes I put the butter on a plate near my oven if I’m using the oven for something else—even just a little heat helps speed it up. If you try to use the microwave to soften that butter, be extremely careful as the slightest bit of melted butter can ruin your entire creaming process. Try slicing the stick of butter into 8 equal pieces (8 Tablespoons), placing on a plate, and microwaving for 2 seconds. Stop. 2 seconds more. Stop. But I urge you to just do it the old school way. The one where patience is needed. The microwave is one risky method.

Room Temperature Eggs

It’s also super imperative for eggs to be at room temperature when the recipe calls for it. A lot of this is because of air bubbles again. When you beat or whisk an egg, the egg’s protein traps the air bubbles. And while baking, the bubbles expand in the heat of the oven. And, again, air bubbles expanding = lighter textured baked good. Air trapping is at its peak when the eggs are at room temperature. Ever notice that it’s much quicker to whip, beat, or whisk eggs when they’re room temperature? They come together so much easier and actually whip to a higher volume! That’s because they’re more loose, for lack of better words. The whole air trapping business isn’t the only reason why we use room temperature eggs in baked goods. Adding cold eggs to a room temperature fat (like creamed butter and sugar) could shock, harden, and curdle that fat. This would ruin the creamed mixture, the entire base of your recipe. If you bake the recipe with this ruined creamed mixture, you’ll have a bunch of little holes in your cupcakes from the hardened butter pieces. Don’t sabotage your recipe! How to bring eggs to room temperature: It’s easy! Simply place the eggs in a bowl of warm water for 10-15 minutes. I usually do this while I’m getting other ingredients ready. Do not use piping hot water– you don’t want to cook those eggs.

Room Temperature Yogurt, Cream Cheese, Milk, Etc.

A lot of cake, cupcake, or bread recipes starting with room temperature butter call for other dairy ingredients like milk, cream, yogurt, etc. The emulsion begins with the butter, sugar, and eggs but it doesn’t stop there. It continues with the rest of the ingredients. To keep your batter smooth and the emulsification seamless, make sure the rest of the recipe ingredients are room temperature as well. Like in my recent Greek yogurt pineapple bars = all room temperature. Or in cakes, cupcakes, breads, everything! Good rule of thumb: if the recipe calls for room temperature or melted butter, the rest of the ingredients should be room temperature as well unless otherwise specified. How to bring these ingredients to room temperature: no shortcuts here. Simply take these ingredients out of the refrigerator when you take out the butter to soften, about 1 hour before beginning the recipe. Here are the blueberry muffins pictured today. I’ve said it a billion times and I’ll say it again: when it comes to baking, it pays off to be a perfectionist. Pay attention to temperature. Temperature is a reason your recipe will or won’t turn out. Always follow the recipe. Do you understand the importance of room temperature ingredients now? Hope so! Further reading:

My 10 Best Baking Tips Baking Powder vs. Baking Soda How to Properly Measure Baking Ingredients Dutch-Process vs. Natural Cocoa Powder My 10 Best Cupcake Baking Tips and How to Fill Cupcakes Room Temperature Ingredients Make a Difference  - 10Room Temperature Ingredients Make a Difference  - 99Room Temperature Ingredients Make a Difference  - 89Room Temperature Ingredients Make a Difference  - 75Room Temperature Ingredients Make a Difference  - 10Room Temperature Ingredients Make a Difference  - 27Room Temperature Ingredients Make a Difference  - 79