Combine crumbs, margarine, peanuts and granulated sugar; press onto bottom and 1-1/2 inches up sides of 9-inch springform pan. Bake at 350F degrees, 8 minutes.
Combine cream cheese, brown sugar, flour and vanilla, mixing at medium speed on electric mixer until well blended. Add peanut butter; mix well. Add eggs, one at a time, mixing well after each addition. Reserve 1/4 cup peanut brittle. Blend in remaining peanut brittle and sour cream to cream cheese mixture; Pour over crust. Bake at 350F for 50 minutes.
Combine sour cream, brown sugar, peanut butter and vanilla; mix well. Spread over cheesecake; sprinkle with reserved peanut brittle. Continue baking 5 minutes. Loosen cake from rim of pan; cool before removing rim of pan. Chill.
Makes 10 to 12 servings.
Cajun Country -- New Iberia, Louisiana