How Much Store-Bought Frosting You Actually Need For Your Cake

Homemade frosting is undeniably better than its store-bought counterpart. However, sometimes you want to focus all of your energy on the homemade cake and just buy a premade jar of frosting to go with it. But, exactly how much store-bought frosting will you need?

If you're making a 9-inch two-layer cake — such as Tasting Table's classic yellow cake with chocolate frosting — you'll need 4 cups of frosting, which will cover the outside as well as the middle layer. Most store-bought frosting cans (including Betty Crocker and Pillsbury) contain two cups (16 ounces) of frosting, so you'll need two cans — or three if you want extra frosting on hand in case of any mess-ups or if you plan to include any decoration or writing on the cake. This is also the same amount of frosting you'll need for a 9-by-13-inch sheet cake, such as our Speculoos Cookie sheet cake.

Meanwhile, if you're making a 9-inch three-layer cake — such as our lemon poppyseed cake — you'll need 5½ cups of frosting, which is just under three containers of frosting. Since there should be a little extra, you have some wiggle room, but you can always buy a fourth container if you want more leeway. Finally, if you plan on making a cake that has more than three layers, you can stick to the rule of thumb of adding 1½ extra cups of frosting per layer. 

Now that you know how much frosting to buy, you may be wondering if there are any ways to make the store-bought frosting taste a little bit more homemade — and there are. One easy way to upgrade the frosting is to simply use a hand mixer to whip it — this will give it a lighter and more airy texture while still remaining plenty creamy.

If the texture still isn't right, there are more hacks to keep in mind. If the frosting is too thick, you can thin it out by adding a little bit of milk. Start with one tablespoon at a time and judge from there. If the frosting is too thin, you can add sifted powdered sugar. Start with a ¼ cup and go from there. A common problem with store-bought frostings is that they may be too sweet for your tastes — you can fix this with eight ounces of cream cheese, which will tone down the sweetness while also making the frosting even richer in texture.