Easy chocolate birthday cake

Directions

1. Preheat oven to 350 ºF
2. Prepare two 7 inches cake pans (butter and flour the bottom and the sides of the pans)
3. In a large bowl, place butter and sugar, and mix well
4. Add eggs one by one
5. Add flour, cornstarch and baking powder, and beat until combined
6. Pour batter into pans and bake for 25 minutes
7. Leave the cakes in their pans on a wire rack for 10 minutes and then turn out to cool.
8. If you are going to prepare 4 layers as in the pictures, carefully wash the cake pans, and repeat the whole process
9. The cakes can be frozen until needed
10. Now we are going to prepare the chocolate buttercream
11. Using and electric mixer, cream butter and sugar, until light and fluffy (about 5 minutes). Add melted chocolate, that shall be cool, and mix well. Now the buttercream is ready to use
12. Fill the cake layers with chocolate buttercream, and then frost it with a thin layer of buttercream
13. Place the cake in the fridge for 15 minutes to set
14. Place the remaining chocolate buttercream on a piping bag fitted with a medium sized round tip
15. Create a row of dots (vertical), as shown on the pictures
16. Using a spatula, spread every dot to the right, in one motion (or to the left if you are left-handed). Clean the spatula between every swipe
17. Once you have spread one row of dots, add another row of dots and repeat the pattern until the whole cake is covered with "petals"
18. If you are not going to eat the cake on the same day, please avoid keeping it in the fridge if possible, so that the chocolate buttercream remains creamy