1. Preheat oven to 350 degrees F. Thoroughly coat a standard-sized muffin tin with cooking spray.
2. With a mixer, beat together butter and sugars on medium speed until light and fluffy, about 3-5 minutes. Add in dry pudding mix, eggs, and vanilla extract, and beat on medium speed for an additional 2 minutes until silky and smooth. Meanwhile, whisk together the flour, baking soda, and salt. Add the dry ingredients to the wet ingredients and mix until just combined. Stir in the chocolate and peanut butter chips.
3. Using a medium cookie scoop, drop about 1.5 tablespoons of cookie dough into the bottom of the muffin tin, and press down to flatten. Top with a tablespoon of chocolate ganache (recipe follows) and then top with another scoop of cookie dough. Bake for 18-20 minutes, until the edges are just browned. As soon as they come out of the oven, run a knife around the edges to make for easy removing later. Cool completely before removing from the muffin tin, using a knife around the edges to help loosen.

For the Sweet Milk Chocolate Ganache

1. Place chocolate chips in a glass or heat-proof bowl. In a medium saucepan, whisk the heavy cream, vanilla, and sugar and bring to a simmer. Pour over the chocolate chips, let sit for 5 minutes, then whisk until completely smooth. Chill in the fridge for 1 hour or until the ganache sets up and reaches a thick, frosting consistency.