Step 1

Preheat oven to 350 degrees F. Line 2 regular muffin tins with cupcake liners.

Step 2

Mix together the cake mix, milk, eggs, oil and Greek yogurt until smooth. Spoon batter into cupcake pans, filling the liners 1/2 full.

Step 3

Place a Reese's PB cup into the center of the batter in each cup (it's okay if the the tops of the Reese's are showing, like photo above).

Step 4

Bake cupcakes for 16-20 minutes or until done. Allow to cool completely before frosting.

Step 5

Beat together butter, and peanut butter and mix until smooth.

Step 6

Add powdered sugar and vanilla and beat again until combined.

Step 7

Add milk and mix until light and fluffy. (Add more milk or powdered sugar if needed to make the frosting thicker or thinner).

Step 8

Frost cupcakes (I used a wilton 1M tip in the photos above).

Step 9

Chop up the remaining pieces of Reese's and gently press into frosting.

Step 10

Store leftover cupcakes, covered, in the fridge for 3-4 days.