In a large mixing bowl, beat together 1 1/4 cup peanut butter, 1 cup powder sugar, 1 1/2 sticks softened butter and vanilla until smooth.
By hand mix in 3 cup chopped pretzels, 1 cup powdered sugar and 1/2 cup chocolate chips. Stir until fully moistened.
Line a 9 x 9-inch pan with aluminum foil and spray lightly with cooking spray.
Press the mixture evenly into the pan.
In a microwave safe bowl, melt the remaining chocolate chips and 3/4 cup peanut butter. Stir until completely smooth. Pour over the pretzel bars and spread evenly.
Sprinkle the top with the remaining 1/2 cup broken pretzels and chopped peanuts.
Refrigerate for at least 4 hours to set.
Cut into squares and serve. Store chilled.