Warm apricot preserves in the microwave for 30 seconds. Brush preserves all over the crust.
In a small bowl, combine ricotta cheese and confectioners' sugar. Mix well and spread mixture all over pie crust, to within 1/4-inch of the edges. Top ricotta with plum slices, making slightly overlapping rows. Sprinkle peanuts over top.
Bake 10 to 12 minutes, until crust and peanuts are golden brown.