Preheat oven to 325 degrees
In a small bowl, melt butter and chocolate together in the microwave. Begin with 30-second intervals, stirring in between, until completely melted.
Cream melted chocolate and sugar together in a medium-sized mixing bowl.
Add in vanilla and eggs, beating one at a time until completely incorporated.
Mix flour, cocoa powder, salt, and espresso powder until combined.
Stir in M&M’S® Milk Chocolate Ghouls Mix Candies.
Using a large cookie scoop, add cookie dough to pan and place in oven.
Once in the oven, drop the oven temperature to 300 degrees and bake for 16-19 minutes.
Make sure to preheat oven to 325 before each new batch.