Position the square cake: Place the square cake on a serving platter so it looks like a diamond (one point facing downward). Cut the round cake in half: Using a sharp knife, slice the round cake ...

Fold in semisweet chips send the pan into the oven. After it bakes and cools, lift out the square, cut the cake in half one way, then cut thick perpendicular slices. Arrange them on a cake platter ...

Cut the cake into 25 equal squares (each 4cm/1½in square). You may need to cut off the edges if they have rounded and pulled away from the sides of the tin - all the edges must be straight and neat.