Preheat the oven to 350 and prepare a baking sheet with parchment. Set to the side.
Toast the almonds in a small, non-stick pan. Toast the almonds until they are fragrant and golden brown. Set them to the side.
In a medium-sized bowl, mix the flour, cocoa powder, espresso powder, baking soda, and salt. Set to the side.
In a large bowl with a hand mixer or in a stand mixer with a paddle attachment, cream the sugar with the butter until light and fluffy, about 2-3 minutes. Scrape down the sides of the bowl as needed, then add in the egg and egg yolk, followed by the vanilla.
Mix in the chocolate chips, mini marshmallows, and toasted almonds. Fold them in using the mixer or with a rubber spatula.
Scoop the cookie dough into balls using a cookie dough scooper. Top the cookie dough balls with extra toppings if desired. Bake the cookies in the oven for 10 minutes.
Let the cookies cool on the pan for a few minutes before transferring them to a cooling rack.
