What would happen if you used 9x9 inch cake pans a recipe calls for 13x9 pans?

If you use 9x9 inch cake pans instead of 13x9 inch pans for a recipe, your cake will be significantly smaller and thicker. Here's why:

* Less surface area: 9x9 inch pans have a much smaller surface area compared to 13x9 inch pans. This means your batter will spread out less, resulting in a thicker cake.

* Baking time: You'll need to adjust the baking time significantly. Since the cake is thicker, it will take longer to cook through. You might need to bake it for 10-15 minutes longer, or even more depending on your oven.

* Density: The thicker cake will be denser than intended. This might affect the texture and overall taste.

Here are some tips for adapting the recipe:

* Double the recipe: The easiest solution is to double the recipe, but this might be impractical.

* Reduce the batter: You can reduce the batter by about 1/3 to compensate for the smaller pan size.

* Adjust baking time: Start by checking the cake after the recipe's recommended baking time. You'll need to add extra time in small increments until the cake is fully cooked.

* Use a toothpick: Insert a toothpick into the center of the cake. If it comes out clean, the cake is done.

Important note: Always adjust the baking time carefully, as overbaking can lead to a dry and crumbly cake. It's best to check the cake frequently during the last few minutes of baking.

It's always recommended to use the pan size specified in the recipe. However, with some adjustments, you can still achieve a delicious cake with a 9x9 inch pan.