Put the milk on the stove to boil. Add the sugar to it. Beat the starches in 4/5 cup (200 ml) of it. Pour it back into the boiling milk slowly, so the cream doesn't turn to lumps.
Arrange the biscuits in a cake form to cover its bottom entirely. Pour on the hot cream. Cover completely with round slices of bananas.
Repeat this process until you've formed 3 biscuit layers. Pour cream generously over the cake.