2) Mix the sugar and biscuit mix, then cut in the peanut butter.
3) Beat the egg and milk together with a fork and beat into the biscuit mixture for 1/2 minute with a spoon.
4) Pat the mixture into greased 9-inch cake pan and spread evenly with the marmalade.
5) Bake in the preheated oven for about 25 minutes.
6) Drizzle with Vanilla Frosting when the cake is still warm.