I found this article online and made a few corrections and additions, but it has great information.
These baking mistakes threaten your beautiful bundts, bread, and bar cookies. Here’s what you should do instead…
In cooking, you’re encouraged to riff: Edamame in your stir-fry? Sure! A splash of rice wine vinegar in your pan sauce? Why not! Curious about herbes de Provence in your chicken rub? Give it a whirl!
In baking, however, creativity should be directed toward what you decide to make and how you decorate it—not how you cook it. That’s because baking is a science; cooking is an art. Science has rules. Art? Not so much.
You don’t read the recipe.
As you do with any IKEA furniture, you should read through the steps and gather your tools before you start mixing and whipping. Otherwise, you might get started and realize you’re one short a cup of cocoa powder of what your recipe needs. Or worse, you’ll start mixing up the dough for the birthday party you’re going to tonight and then realize it’s supposed to chill overnight. Oops!
The fix: Pull your recipe up on your phone, or get it from your cookbook. Read the ingredient list, and assemble everything that’s listed. Then, read the directions. You can even go so far as to “pretend” each step. This way, you can double check you have every ingredient and every appliance or tool you need.
You decide to wing it instead of measuring the ingredients.
The “a little of this, a little of that” mentality may suit you well in cooking, but in baking, it could backfire. After all, consider this: cookies, cakes, and bread contain many of the same ingredients: eggs, flour, sugar, butter, for example. In the right ratios, they make a specific type of baked good. In the wrong ratios, they could be a disaster. That’s why it’s vital to measure every ingredient, from the flour to the tiniest bit of cinnamon.
The fix: Use your measuring spoons and cups. You need the right ratios to get the best results. Save the winging it for your salad dressing.
You don’t respect the comma.
Has the comma in “1 cup flour, sifted” ever confused you? What about the comma in “1/2 cup pecans, chopped”? The comma is telling you something very important. Do you know what?
The fix: The comma is telling you to first measure the ingredient and then perform the task. Measure the cup of flour, then sift it. Or measure the half cup of pecans, then chop them. There’s a big difference between half a cup of chopped pecans and half a cup of pecans that were measured, then chopped. It can dramatically affect your final result.
You use liquid measuring cups for dry ingredients (or vice versa).
Liquid measuring cups and dry measuring cups measure things differently. Though it’s not a significant amount, it’s enough that it could affect the texture of your final product.
The fix: Use wet measuring cups (typically, the glass type you pour from) for everything liquid: water, oil, honey, milk, molasses, corn syrup, etc. Use dry cups for everything else, from flour and sugar to chocolate chips and yogurt. With the dry cups, be sure to use a flat surface, like the back of a knife, to swipe across the top of the cup to remove excess before adding to the batter.
You dip your measuring cup into the flour.
Dipping a measuring cup into a bag or jar of flour packs the flour into the well of the measuring cup. It may seem like the easiest way to scoop flour, but you’re actually getting more flour than you really need. Too much flour will turn into dense bread, hard cookies, and stiff cakes.
The fix: You need the same amount of flour each time to get consistent results, and you can do this in two ways: The less accurate option is to use a spoon to lightly scoop flour into a dry measuring cup, then use a flat edge (like a knife) to level off the flour. The most accurate way to measure flour is with a digital scale. A cup of all-purpose flour should be 130 grams.
You don’t preheat your oven.
We’ve all been there: You’ve just finished rolling out a tray full of cookie dough only to realize your oven is cool as a cucumber. So to save time, you turn the oven on and just stick the pan in any way. Bad idea. The quick and sudden heat is an important part of the baking process. If the dough heats slowly, you may have a mess on your hands.
The fix: If you realize the oven isn’t pre-heated when you’re ready to bake, just let the dough or batter sit while the oven heats up. Most ovens can be heated in about 10 minutes time. If you’re working with a temperature-sensitive dough, pop it in the fridge until the oven is ready.
You’ve never measured your oven’s temperature.
I have some bad news: Your oven could be lying to you. Just because it says 350°F doesn’t mean it really is. That means your brownies or pastries may not bake properly because your oven could be too hot, or even too cool. And 25°F in one direction can make a big difference in the final product.
The fix: Invest in an oven thermometer. Hang it from the grates in your oven the next time you turn it on. Let the oven pre-heat fully, and then see what the thermometer says. That will give you an idea of how correct your oven is—and how you need to adjust the oven when you bake in it.
You substitute baking powder for baking soda.
They might share a similar name, and they even look similar out of the box. But baking soda and baking powder are quite different. Baking soda must have an accompanying acid (lemon juice, vinegar, buttermilk, for example) to activate it; baking powder, on the other hand, has that acid already. If you use the wrong one, your baked goods will take a hit.