To prepare a strawberry chocolate layer cake recipe, first you need to prepare the cake batter. First, mix the flour, baking powder, sugar, and salt together. Then, add the wet ingredients to the dry ingredients and mix until the batter is just combined. Next, pour in the milk and beat the mixture with an electric mixer until it's light and fluffy. Add the vanilla and the chocolate chips. Finally, stir in 1 cup of the strawberry puree. Pour the remaining batter into the prepared cake pan and bake for 35 to 40 minutes or until toothpick inserted in center comes out clean. Allow cake to cool for 10 minutes before cutting into squares.