Preheat your oven to 350°F (175°C). This ensures that your brownies bake evenly.
Line your 9x13-inch baking pan with parchment paper, leaving some overhang on the sides for easy removal later.
In a large mixing bowl, combine the flour, dark brown sugar, baking soda, and salt. Whisk together until combined.
In another bowl, melt the chilled unsalted butter and chopped unsweetened chocolate together. Let it cool slightly before adding honey, milk, vanilla extract, and 1 egg. Stir until well combined.
Pour the wet ingredients into the dry ingredients and mix until just combined. Do not overmix!
Pour the brownie batter into the prepared baking pan, spreading it evenly with a spatula. Bake for 25-30 minutes, or until a toothpick inserted comes out with a few moist crumbs.
While the brownies are baking, prepare the cream cheese layer. Combine softened cream cheese, flour, baking powder, salt, instant coffee, unsalted butter, brown sugar, eggs, and vanilla. Beat until smooth and creamy.
Once the brownies are done baking, let them cool for about 10 minutes. Spread marshmallow fluff evenly over the brownies, then pour the cream cheese mixture on top.
Return the pan to the oven and bake for an additional 20-25 minutes, or until the cream cheese layer is set and lightly golden on top.
Allow the Smores Brownies to cool in the pan for at least 30 minutes before lifting them out using the parchment overhang. Cut into squares and serve warm or at room temperature.
