So I cheated a bit with these. I used a basic yellow box cake mix. Baked it in two pans. Sliced each into 8 pieces, sliced those down the middle. Put dulce de leche between layers, cut it into smaller squares and frosted with store bought classic white frosting. Put some dulce de leche in the microwave for a few seconds and drizzled on top. Yum.
This is as far as I got when my camera battery died. Sorry :(