1 (12 oz.) box vanilla wafers
1/2 c. sugar
2 tbsp. (1/4 c.) butter, melted

FILLING:

1 lb. cream cheese, room temp.
1 1/2 c. sugar
1 (6 oz.) jar creamy peanut butter (2/3 c.)
5 eggs
1/2 c. sour cream
2 tsp. fresh lemon juice
3/4 - 1 c. semi-sweet chocolate chips

TOPPING:

1 c. sour cream
3/4 c. semi-sweet chocolate chips, melted
1/2 c. sugar

For crust: Preheat oven to 350 degrees. Butter bottom and sides of 9 inch springform pan. Combine all ingredients in food processor and process to uniform crumbs. Press mix onto bottom and sides of pan. Bake for 10 minutes. Cool slightly.

For filling: Combine all ingredients except chocolate chips in processor and blend until smooth. Add chips and mix 10 seconds using on/off turns. Spread filling in crust. Bake until center of filling is firm, about 70-80 minutes. Let stand at room temperature for 15 minutes before adding topping. Keep oven on at 350 degrees.

Meanwhile, prepare topping. Blend all ingredients. Spread over cheesecake. Bake 10 minutes. Let cake cool, then refrigerate at least 3 hours before serving.