Converting from Square Baking Pan to 9x13 Semolina-Sesame Cake

Craig B. (Q&A ID 5631)

How do I convert your semolina-sesame cake from the square baking pan in the recipe to a 9-by-13-inch metal baking pan? I don't own square pans. What should I multiply the ingredients by? Thank you and have a great day,

Elizabeth M. (Q&A ID 13500)

Hello Craig,

The King Arthur Flour and Epicurious websites have good information for converting recipes to different cake pan sizes. The Epicurious information is behind a paywall. Look for an article on the King Arthur site called "The Essential Alternative Baking Pan Sizes."

Best,

The Milk Street Team

Craig B. (Q&A ID 5631)

Uhhh the King Arthur page asks me to do a bunch of geometry mumbo jumbo. I just want to know what to multiply the ingredients in the recipe for my 9*13 rectangular pan. I would never give Epicurious any money, so definitely wouldn’t go there. Thanks

Lynn C. (Q&A ID 662)

Hi Craig -

The amount of batter in a cake pan is an important part of the recipe. Too much batter, and the cake could sink in the middle or overflow. Too little batter, and you’ll end up with a thin, shallow and dry cake (the moisture will evaporate too quickly). It’s smart to be precise about pan sizes because, for example, a mere 1-inch difference in pan area between an 8-inch square pan and a 9-inch square pan ends up being big – a 14-square inch difference, making the 9-inch pan 25% larger. So, unfortunately, the best way to switch from one cake pan to another is to do a mathematical conversion using the square area of the pan.

The area of a 9x9x2 pan is 81 square inches and holds 10 cups of batter. The area of a 9x13x2 pan is 117 square inches and holds 14 cups of batter (you can find this information in the article on the King Arthur website that Elizabeth mentioned). As you can see, this is not a simple conversion in which we can say, “just double/triple the ingredients.” Instead, we need to do the following:

1. Divide the area of the large pan by the area of the smaller pan that the recipe calls for. (e.g., 117/81 = 1.44)
2. Multiply the answer from step 1 (your conversion factor) with the amount of each ingredient in the recipe. (e.g., 1.44 * 170 grams = 244.8 (245) grams semolina flour)

Keep in mind that it’s easier to scale a recipe up or down if you weigh ingredients, especially using metric measurements. Measuring by volume is not hard, but it takes a little more work to halve a measurement like 1/3 cup (the easiest way would be to break it down into smaller units, like tablespoons, and then do your math).

Best of luck,

The Milk Street Cooking Team