Place Reese?s Cups in the freezer to harden.

In a stand mixer bowl, cream together butter, peanut butter, and sugars until light and fluffy. Scrape sides of bowl.

Add eggs and vanilla extract. Beat until well-combined.

In a separate bowl, whisk together flour, cornstarch, baking powder, baking soda, and salt.

Gradually add flour mixture to batter while stirring on low speed until completely combined.

Stir in chocolate chips.

Place dough in refrigerator to chill for 15-30 minutes.

Remove chilled dough and Reese?s cups from freezer. Remove peanut butter cups from wrappers.

Scoop dough by heaping 1 ? Tbs-sized spoonful and press peanut butter cup sideways into the center. Form dough around the peanut butter cup until completely concealed.

Roll into round balls and place on a wax-paper lined plate or tray. Return cookie dough balls to refrigerator for 15 minutes.

Preheat oven to 375?F (190?C) and line cookie sheets with parchment paper.

Place cookie dough balls at least 2" apart on cookie sheet and bake for 14 minutes, or until edges are just beginning to turn golden brown.

Allow cookies to cool completely on cookie sheet before serving.