Preheat oven to 350°F. Line a 9x9 metal baking pan with parchment paper and spray with baker's spray.

In a large bowl, combine fudge brownie mix, eggs, vegetable oil, and water. Whisk until smooth.

Spread the brownie batter evenly into the prepared pan. Bake for 30-33 minutes until a toothpick comes out with moist crumbs.

Cool the brownies completely. Meanwhile, heat treat the flour by spreading it on a baking sheet and baking at 350°F for 5-7 minutes.

In a mixing bowl, beat softened butter, brown sugar, granulated sugar, and vanilla until fluffy.

Add heavy cream and salt. Mix until combined.

Gradually add heat-treated flour, mixing just until incorporated. Fold in mini chocolate chips.

Once the brownie layer is cooled, scoop cookie dough over the surface and spread evenly with a spatula, avoiding mixing with the brownie layer.

Sprinkle mini M&M’s candies over the cookie dough and gently press them down.

Refrigerate for 30 minutes. Lift out of the pan using parchment and slice to serve.