Preheat the oven to 350F. Lightly oil a 9-inch square or round cake pan.
Combine the flour, baking powder, sugar, and salt in a mixing bowl and stir together.
Combine the apple sauce, rice milk, and peanut butter in another bowl and whisk together until smooth. Pour into the flour mixture and stir until fairly well blended, then whisk the mixture until smooth.
Stir in the chocolate chips and optional peanuts. Pour into the prepared pan. Bake for 25 to 30 minutes, until golden on top and a knife inserted into the center comes out with chocolate, but no batter.
Allow to cool to room temperature or just warm, then cut into squares or wedges to serve.