How to Cut a Heart‐Shaped Cake

Creating a Heart Shape

Bake an 8 in (20 cm) square cake and an 8 in (20 cm) round cake. Use a boxed mix or your favorite cake recipe to mix up your batter. Then, divide the batter into 2 cake pans, one 8 in (20 cm) square cake pan and one 8 in (20 cm) round cake pan. Bake the cakes as directed in your recipe. If you’re using an 9 by 13 in (23 by 33 cm) pan instead of an 8 in (20 cm) square pan, trim the cake to an 8 by 8 in (20 by 20 cm) shape. However, keep in mind that you’ll likely need additional cake mix to make both cakes. You can bake 2 different cake flavors if you like. For instance, you might make a strawberry round cake and a chocolate square cake.

Allow the cakes to cool to room temperature before you handle them. Don't try to cut the cakes while they're hot because they will crumble and break up. Instead, allow the cakes to cool on a cooling rack or towel until they feel room temperature to the touch. If you have time, put your cakes in the refrigerator or freezer to get them cold. This will make it easier to work with them.

Position your square cake as a diamond on your serving platter. Place your serving platter on your work space. Then, transfer your square cake onto the lower portion of the platter. Turn the square cake so that it looks like a diamond from your perspective. One corner of the square cake will point toward you. This corner will form the bottom of the heart.

Cut the round cake into 2 equal-sized semicircles. Place the round cake on a clean surface that you can use for cutting. Position a large cake knife directly over the middle of the cake. Slowly slice into the cake to divide it into 2 equal halves. Don’t slice too quickly because you might accidentally cause crumbs or clumps to break off.

Place 1 semicircle on the top-left side of the diamond. Pick up 1 of the halves of the round cake. Transfer the semicircle to the serving platter. Line the flat side of the semicircle up with the top-left side of the square cake to make 1 side of the heart. Be careful when you’re handling the cake because it’s easy to break it.

Put the other semicircle on the top-right side of the diamond. Pick up the other half of the round cake and transfer it to the serving platter. Line the flat side of the semicircle up with the top-right side of the diamond. Place the cake down to complete the heart. It’s okay if the heart doesn’t look perfect. You can trim the square cake to make the pieces fit together, if necessary.

Trim the top of the square cake to make the semicircles meet if necessary. If the 2 semicircles don’t touch in the center of the heart, you may want to trim the square cake to bring them closer together. Move the semicircles away from the square cake. Then, use a cake knife to shave about a millimeter of cake off of the top sides of the square cake. Continue to shave the cake until the semicircles touch in the middle of the heart. You might not need to trim your square cake at all. If you do need to trim it, expect to cut off a few millimeters from each side, at the most.

Use your knife to trim the bottom edges of the square if necessary. Check to make sure that the sides of your heart look even from the round part down to the bottom. If the cakes don’t line up on the side, use your cake knife to shave down the square cake so that there’s a smooth line down the side of the heart. You may not need to shave the bottom part of the square cake. If you do end up trimming it, expect to remove about 2-3 millimeters of cake from each side.

Spread icing between the cake pieces to hold the heart together. Move the semicircles away from the square cake so you can apply icing between the pieces. Then, use a butter knife to spread a thin layer of icing onto the top sides of the square cake where the 2 cakes join. Push the semicircles into the icing, which will hold the pieces in place. The icing between the square cake and the semicircles should be about 1-2 mm thick. The icing will help keep your heart together as you decorate it.

Use a butter knife to apply icing to the cake. Scoop out the icing using the flat side of your butter knife. Start applying the icing in the center of the cake and spread it out toward the sides. Get more icing on your knife as necessary to cover the entire surface of the cake. Then, use the flat side of your knife to even out the icing. If you want to decorate your cake, try adding a border, writing on the cake, or adding candy or sprinkles. If the cakes are different heights, you can even them out when you ice the cake. Simply apply more icing on the cake that’s lower until the surface of the heart looks even.

Slicing the Cake for Serving

Use a cake knife to cut vertically down the middle to create 2 even sides. Line up your knife with the dip between the curves of the heart. Slice down to the point at the bottom of the heart. Do your best to keep the sides as even as possible. It’s okay to make small cuts down the cake if that’s easier for you. However, keep in mind that this might cause clumps of cake to break off and stick to your knife.Variation: If you’re not worried about all of the slices being even, it’s okay to cut triangle slices. Start cutting in the middle of 1 side of the heart. Make a slice from the center of the cake out to the side of the cake with your cake knife at an angle. Then, cut the other side of the triangle piece from the center of the cake to the side. Continue to cut triangle pieces until your cake is sliced. Keep in mind that the pieces will likely vary in size.

Make vertical cuts every 2 in (5.1 cm) across each side of the cake. Shift your knife about 2 in (5.1 cm) from the center line. Slice vertically down the cake again. Then, repeat on the other side of the center line. Continue to slice the cake horizontally every 2 in (5.1 cm) until you reach the edges of the cake. Alternate from side-to-side as you cut to help you keep the slices as even as possible. You will have some slices along the edges that are a different shape, and that's okay.Variation: For small slices or a small cake, make your cuts every 1 in (2.5 cm).

Cut the cake horizontally across the middle to divide it into 2 parts. Find the center point at the middle of the cake. Then, align your cake knife with the center of the cake. Make a horizontal slice across the middle to divide the cake into a top and bottom half. Slowly cut the cake since you’ve already sliced it vertically. It may be easier to cut each vertical section individually so the sides of the pieces don’t start to crumble.

Slice the cake horizontally every 1 in (2.5 cm) from the middle cut. Move your knife 1 in (2.5 cm) above the slice across the middle. Then, make another slice from side to side. Next, position the knife 1 in (2.5 cm) below the line you cut down the middle and slice the cake again. Continue to make 1 in (2.5 cm) horizontal slices until you’ve cut the entire cake. Most of the slices will be roughly the same size, which is 2 by 1 in (51 by 25 mm). However, you will have edge pieces that are a slightly different shape to accommodate the shape of the heart.