Preheat oven to 350°F

Coarsely chop walnuts and pecans. On a parchment paper lined baking sheet, place nuts in a single layer and bake 7 to 9 minutes until toasted and aromatic. Set aside and cool completely.

In a small saucepan, melt butter and chocolate on low heat. Set aside and cool completely.

In a mixing bowl, whisk together eggs and sugar until light and fluffy.

Add cooled chocolate mixture and stir until glossy.

Add the flour, baking powder and salt and mix until just incorporated. Stir in chocolate chips and marshmallows.

Let dough chill for 20 minutes in the refrigerator so that it is easier to scoop.

Use a 1 3/4 inch diameter scoop to drop spoonfuls of dough on the prepared baking sheets, spacing them at least 1 1/2 inches apart. Wet your fingertips lightly with water and gently flatten the cookie dough a little bit.

Bake for 10-12 minutes, until the tops begin to crack and look glossy. Cool the cookies for 10 minutes before removing them from the baking sheets.