Ingredients

BROWNIE CRUST:1/4 cup butter, cubed3 ounces unsweetened chocolate1 cup packed brown sugar2 large eggs, room temperature1-1/2 teaspoons vanilla extract2/3 cup all-purpose flour1/8 teaspoon baking powder1 ounce semisweet chocolate, choppedFILLING:1 jar (12 ounces) creamy peanut butter11 ounces cream cheese, softened1 cup packed brown sugar3 large eggs, room temperature, lightly beaten1/2 cup sour creamTOPPING:3/4 cup sour cream2 teaspoons sugarOptional: Salted peanuts and melted semisweet chocolate

Preparation

In a microwave, melt butter and unsweetened chocolate; stir until smooth. Set aside. In a large bowl, beat brown sugar and eggs until light and fluffy, about 4 minutes. Beat in chocolate mixture and vanilla. Combine flour and baking powder; gradually add to batter and mix well. Stir in chopped chocolate.

Spread 1 cup into a greased 9-in. springform pan. Cover and refrigerate remaining batter. Place pan on a baking sheet. Bake at 350° for 17-19 minutes or until a toothpick inserted in the center comes out clean. Cool on a wire rack for 5 minutes; place in freezer for 15 minutes.

For filling, in a large bowl, beat the peanut butter, cream cheese and brown sugar until smooth. Add eggs and sour cream; beat on low speed just until blended. Spread remaining brownie batter about 1-1/2 in. high around sides of pan, sealing to baked crust.

Pour filling into center. Bake at 350° for 45 minutes or until center is almost set.

For topping, combine sour cream and sugar; spread over filling to within 3/4 in. of edges. Return cheesecake to the oven; turn oven off and let stand for 5 minutes. Cool on a wire rack for 10 minutes. Carefully run a knife around pan to loosen; cool 1 hour longer. Refrigerate overnight. If desired, top with peanuts and drizzle with melted chocolate. Refrigerate leftovers.