1-First Step: Mise en Place: Gather all your ingredients and preheat the oven to 350°F (175°C). Line two baking sheets with parchment paper. In a medium bowl, whisk together the flour, cocoa powder, 1 tablespoon hot cocoa mix, baking soda, and salt. This dry mix ensures even flavor distribution in your mini cookies.

2-Second Step: Cream the Wet Ingredients: In a large bowl, beat the softened butter, granulated sugar, and brown sugar with an electric mixer on medium speed until light and fluffy, about 2-3 minutes. Add the egg and vanilla extract, mixing until fully combined. Scrape down the sides to incorporate everything.

3-Third Step: Combine Wet and Dry: Gradually add the dry ingredients to the wet mixture, stirring on low speed until a dough forms. Do not overmix to keep the cookies tender. The dough will be thick and fudgy, perfect for shaping around fillings.

4-Fourth Step: Assemble the Bombs: Scoop teaspoon-sized portions of dough (about 1 tablespoon each). Flatten slightly in your palm, place one mini marshmallow and a pinch (1/4 teaspoon) of remaining hot cocoa mix in the center. Top with another flattened dough piece and gently seal edges to form a ball. Repeat for all.

5-Fifth Step: Bake to Perfection: Bake for 10-12 minutes until edges are set but centers are soft. Cookies will firm as they cool. Let rest on sheets for 5 minutes, then transfer to a wire rack.

6-Sixth Step: Chocolate Coating: Melt chocolate in a microwave-safe bowl in 30-second bursts, stirring until smooth. Dip cooled cookies halfway into chocolate, letting excess drip off. Place on parchment to set.

7-Final Step: Finishing Touches and Serving: Dust with powdered sugar if desired. Serve at room temperature or warm. Store as noted below. Pair with hot milk for a true hot cocoa bomb effect at your next gathering.