

I'm sure you could create your own recipes, but that could potentially involve endless amounts of tinkering and recipe testing. Fun but probably very time consuming!
What I do is search for recipes that I know will work because I recognize certain ingredient combinations I know will work or certain methods that have worked well in the past. For example, for chocolate cakes, I prefer chocolate mud cake recipes (which use large amounts of chocolate) over regular recipes (which use cocoa powder) because they tend to be far more rich, chocolaty, and moist. I also like to take recipes I already have and change a few ingredients to create a new flavor. For instance, in a white almond sour cream cake, swapping out the milk for coconut milk for a coconut flavor.
I also follow lots of baking blogs. There are TONS of wonderful recipes out there that bloggers have formulated and tested and retested to get the perfect cake. Livforcake.com and stylesweetca.com are some of my favorites.

An understanding of the fundamentals is key to creating your own recipes.
1. Type: knowing different types of cakes (shortened, foam and sponge, tortes and flourless, and yeast cakes, etc.) The different cakes call for specific ingredients and ratios (e.g., flour, to fat, to sugar)
2. Baking by weight, not volume: it comes down to ratios, so you have to develop a recipe using weight measurements
3. Baker's percentages and ratios: understand the percentage of parts per hundred of each ingredient. It sounds complicated, but it becomes second nature with a little bit of practice. Flour is always 100%; all other ingredients are a percentage of the flour. Example:
flour: 350 grams (100%)
butter: 280 grams (.80)
sugar: 308 grams (.88)
Some times an ingredient will be more than 100. Cookies frequently have more sugar than flour. My chocolate chunk cookie is 1.10 sugar. But flour is still the base on which all the other ingredients are measured.


Let's say I used a pie crust recipe and decided it wasn't buttery and flaky enough. So I want add more butter. The original crust had .66 butter to flour. So I decide to increase it to .80 fat.
Pie crust ratios I decide to use:
Flour 100
Fat .80
Water .25
Salt .015
I know from experience I like to have 20 grams of flour per inch of pie plate.
I know I need to add 2" to account for the pie plate sides and enough over-hang to crimp the crust
9" + 2" = 11" of pie dough to cover the pie plate
Now that I know the size I need, I calculate the ingredients based on the ratios I decided to use:
20 grams flour x 11" pie plate = 220 grams flour
Flour & fat: 220 x .80 = 176 grams fat
Flour & water: 220 x .25 = 55 ml water
Flour & salt: 220 x .015 = 3.3 grams salt (round down to 3 grams)
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Let's say I need to bake 1 double crust pie and 1 single crust pie. All 9" pies.
9" + 2" = 11" pie plate
I need 3 single crusts
11" x 3 = 33" inches of pie plate to cover
20 grams flour x 33" = 660 grams flour
Flour & fat: 660 x .80 = 528 grams fat
Flour & water: 660 x .25 = 165 ml water
Flour & salt: 660 x .015 = 9.9 grams salt (round up to 10 grams salt)
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I made a blueberry muffin recipe recently. Here's how it reads in my notebook:
375 degrees 20 min
250g flour/12 muffins
#40 scoop; 2 scoops
Muffin batter
100% Central Milling AP Artisan Craft
5% Baking powder
2% Baking soda
1% salt (fine sea salt)
66% baker's sugar, infuse zest 1 lemon
38% butter (plugra)
33% eggs, slightly beaten
80% buttermilk
5% vanilla paste
80-100% fresh blueberries +/- to taste
Topping
300 grams topping/12 muffins
Work butter in with fingers
Chill 10 mins
Equal parts:
- Flour
- Almond flour
- Sugar
- Butter
- .3 water

Okay so then my next question would be how would you know what ingredients to use and what percentage to make them. I'm sorry for all the questions. I've just been struggling with bakers percentage so I really appreciate your help @siftand. Also @cakingandbaking I'm definitely going to try the mud cake.

Nothing wrong with questions--that's how we learn.
Ratio: The Simple Codes Behind the Craft of Everyday Cooking by Michael Ruhlman is one source.
Keep in mind ratios are a GUIDE, a place to start. There are so many factors (wheat variety, protein content, technique, etc.,) that determine the success or failure of a recipe.
Another way to educate yourself, is to convert recipes to metric weight, then calculate the percentages. I do this all the time.
Convert several recipes of the same type (e.g., three different sponge cake recipes); then compare the ratios. Then do the same with other cake types, like pound cake, genoise, chiffon, etc. You will see the sponge cake recipes will be similar in ingredients and ratios. The pound cakes will be very different from the sponge cakes. But all the pound cakes recipes will be similar in ingredients and ratios to each other. You'll begin to understand what defines a sponge cake vs. a pound cake.
The King Arthur Flour website will allow you to select volume, US weight, or metric weight for their online recipes. So that's a good place to pull recipes for analysis.
Analyzing recipes this way will give you an understanding of the necessary ingredients for a particular cake, pastry, bread, or cookie, as well as an understanding of the ratio parameters.
Once you gain some understanding of ingredients and ratios, select a cake recipe you like, but want to improve; bake it exactly as written. Analyze your result; decide on one improvement you would like to make.
Then bake it a second time with ONE revision to create your ideal cake. Say you want it to be moister. Then you might try replacing milk with sour cream. Whatever the revision, 1. Write it down; 2. Stay within the parameters of the ratios.
After a while revisions will become second nature. And you will end up adding your own take on just about every recipe you try. There's a very popular white cake recipe that was once circulated on a blog called Beyond Butter cream. I tried it and thought it was decent enough, but wasn't what I wanted in a go to white cake. So I revised it, one revision at a time. It's now unrecognizable from the original, but my version is what I want in a white cake--both technically, flavor-wise, and texture-wise. By technically, I mean baking it in a sheet pan, reducing mix and bake time to under 30 minutes, and using cake rings to cutout layers. Because seriously, I'm not inclined to set a timer to mix any thing for exactly 90 seconds, prepping multiple cake pans, weighing and dividing batter into several pans, rotating them in the oven, then leveling and torting the layers. Baking is suppose to be fun, not torture.

The link below contains a video of Jacques Pepin eloquently explaining why a recipe shouldn't be followed. His lecture will reinforce your desire to finesse a recipe to make it an expression of you. I think it's one of the best discussions on how we should approach cooking and baking.
http://www.davidlebovitz.com/jacques-pepin-how-following-a-recipe-can-lead-to-disaster/


A MUST for your kitchen is Rose Levy Bernenbaum's "The Cake Bible". This book will have most of the "science" behind cakes and using ratios and how the ingredients affect each other during a bake.
I strongly suggest you get this from the library first, look it over and decide if you wish to purchase the book. I've provided an Amazon link so you can use the information to find the least expensive copy available online:
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