Combine the cookie crumbs and melted butter. Place a spoonful of crumbs in 24 cupcake liners. Press down firmly. Set aside.
In a mixing bowl, beat the cream cheese, sugar, and vanilla until creamy. Add the eggs, sour cream, and flour and beat again.
In a microwave safe bowl, combine the chocolate chips and shortening. Heat for 30 seconds and stir. Repeat until melted. Let cool slightly. Pour into cream cheese mixture and beat until creamy. Spoon into prepared cupcake liners. Bake at 350 degrees for 22-24 minutes. Let cool in pan for 3-4 minutes, then remove to wire rack to cool completely.
In a mixing bowl, beat the cream cheese and peanut butter until creamy. Add the Cool Whip and beat gently with the wire whisk attachment until creamy. Place spoonfuls on top of cooled cheesecake and spread out. Top with Reese's Peanut Butter Cups. Makes 24 cupcake cheesecakes. Keep refrigerated in a sealed container.
Mini cheesecakes baked in paper liners yield a dense, velvety interior beneath a whipped peanut butter topping and chopped confections. Individual portions emerged in American bakeries during the mid-twentieth century as a practical adaptation of traditional springform desserts, offering portion control without slicing. Cream cheese requires complete softening to room temperature before mixing; cold blocks trap air pockets that prevent a uniform emulsion with sugar and eggs. Adding two tablespoons of flour provides a structural matrix of gluten that reinforces the protein network of the dairy, preventing cracks as the miniature cakes cool from 350 degrees. Shortening melted alongside chocolate chips introduces lauric acid and other fats that stabilize the glossy sheen and prevent bloom during storage. Scaling this formulation up or down requires maintaining precise ratios of dairy to binding agents, though doubling the batter is straightforward when mixers possess adequate capacity. Storing the finished cheesecakes in a sealed container within the refrigerator protects the delicate whipped topping from absorbing ambient odors.