Preheat oven to 350 degrees F.

Line a regular size muffin tin with cupcake liners. Spray liners with nonstick cooking spray. Set aside.

Combine all of the Crust ingredients in a large bowl. Mix until well combined. Evenly distribute crumbs between cupcake liners, approximate 2 ½ tablespoons per liner.

Press crumbs into the bottom and ¾ up the sides of each liner using the back of a tablespoon. They don’t have to be even or perfect.

Add butter and baking chocolate to a large microwave-safe bowl and microwave for 1 minute, or until butter is melted, then stir until butter and chocolate are completely smooth. Stir in sugar until smooth. Add eggs and egg yolks then then beat for 1 minute with a hand whisk. Fold in flour just until combined.

Evenly spoon batter into prepared crusts. It’s okay if the batter rises above the top of the graham crackers. Bake for 9-11 minutes, or until the sides are firm but the centers are still soft (but not jiggly).

Remove from oven and top each pie with half of a marshmallow. Broil 6” away from broiler until golden, approximately 1-2 minutes.

Let cool for 1 minute then remove pies using cupcake liners. Serve immediately for a molten center as the center will continue to cook as the pies cool. If you can’t serve immediately, they will still be delicious with a gooey center, just not quite as runny molten.