Heat oven to 350°F. Let cookie dough stand at room temperature 10 minutes to soften. Line 12 regular-size muffin cups with Reynolds® Baking Cups.
In large bowl, break up cookie dough. Add cocoa, vinegar, vanilla and 1/2 cup water. Beat with electric mixer on low speed 2 minutes or until well blended. Spoon about 1/4 cup batter into each muffin cup, filling about 2/3 full.
In a small bowl, beat peanut butter and sugar with electric mixer on medium speed, scraping bowl occasionally, 2 minutes or until well blended; stir in chocolate chips. Spoon or pipe 1 rounded tablespoonful peanut butter mixture in center of each muffin cup.
Bake 23 to 26 minutes or until toothpick inserted in cake around edges comes out clean. Cool 15 minutes; remove from pan to cooling rack. Cool completely, about 20 minutes. Store in covered container.