Preheat oven to 325 degrees F. Lightly spray a 10-inch Bundt pan with cooking spray with flour and set aside.

In a medium bowl combine flour, baking powder, baking soda and salt. Set aside.

In a large mixing bowl, cream butter and peanut butter together until well incorporated. Gradually add sugar, beating on medium speed about 6 minutes or till very light and fluffy. Add vanilla. Add eggs, one at a time, beating on low to medium speed 1 minute after each addition and scraping bowl frequently. Add flour mixture and yogurt, alternating between the two, beating on low speed just till combined. Carefully pour batter into prepared pan.

Bake in preheated oven about 65 minutes or till a wooden toothpick inserted in center comes out clean. Cool in pan or wire rack 15 minutes. Remove from pan. Cool completely on wire rack. Spoon Peanut Butter Glaze over top and down side of cake. Let stand 1 hour to set. Drizzle with cocoa glaze.

Peanut butter glaze: In a small bowl, beat 1/4 cup peanut butter till fluffy. Gradually beat in 1 cup sifted powdered sugar, 3 tablespoons milk, and 1 teaspoon vanilla. Beat in an additional 1/2 cup sifted powdered sugar and enough milk to make icing a drizzling consistency.

Cocoa glaze: In a small bowl, stir 3/4 cup sifter powdered sugar, 1 tablespoon unsweetened cocoa powder, 1 tablespoon margarine or butter, melted and 1 tablespoon water till smooth. Stir in additional sifted powdered sugar or water to make icing a drizzling consistency.