Cream butter, peanut butter, white sugar and brown sugar.
Mix in egg, vanilla and flour to form a soft dough.
Divide dough in half and press each half into a 12” greased round pizza pan.
Bake 7-10 minutes at 350 degrees or until edges are golden brown. Remove from oven.
Completely cover with marshmallows, scatter with chocolate chips and peanuts.
Return to oven for an additional 3-5 minutes until marshmallows puff.
Cut when cool.