Making these S’mores Brownies is a fun and rewarding process. Follow these simple steps to create this dessert masterpiece:

1. Preheat your oven to 350°F (175°C). Line a 9×13 inch baking pan with parchment paper, leaving some overhang for easy removal later.
2. Melt the Butter: In a medium saucepan, melt the unsalted butter over low heat. Remove from heat and stir in the granulated sugar until well combined.
3. Add Eggs and Vanilla: Add the eggs one at a time, whisking well after each addition. Mix in the vanilla extract.
4. Combine Dry Ingredients: In a separate bowl, sift together the flour, cocoa powder, baking powder, and salt.
5. Mix: Gradually add the dry ingredients into the wet ingredients, stirring until just combined. Avoid overmixing.
6. Fold in Chocolate Chips: Add in the semi-sweet chocolate chips, mixing gently to distribute them evenly throughout the batter.
7. Spread the Batter: Pour the brownie batter into the prepared baking pan and spread it evenly with a spatula.
8. Bake: Place in the preheated oven and bake for 30-35 minutes, or until a toothpick inserted in the center comes out mostly clean. Allow to cool for 15-20 minutes in the pan.
9. Prepare the Marshmallow Topping: In a medium saucepan, heat the heavy cream over medium heat until it starts to simmer. Remove from heat and stir in the vanilla bean paste.
10. Toast the Marshmallows: Sprinkle the mini marshmallows evenly over the cooled brownies. Pop them under the broiler for 1-2 minutes until golden and toasted, keeping a close eye to prevent burning.
11. Prepare for Serving: Once toasted, let the brownies cool completely in the pan. Remove from the pan using the parchment paper overhang and place on a cutting board.
12. Slice and Serve: Use a sharp knife to cut your brownies into squares, ensuring they stay intact.