Preheat the oven to 350°F (175°C) and prepare the baking dish by greasing it.

Melt the butter and semi-sweet chocolate together until smooth.

Stir in the granulated sugar, then add the eggs one at a time, mixing well.

Mix in vanilla extract, flour, and salt until completely combined.

Spread half of the brownie mixture in the prepared dish.

In a separate bowl, beat the cream cheese with 1/4 cup of granulated sugar, egg yolk, peppermint extract, and food coloring until smooth.

Spread the cream cheese mixture over the brownie layer.

Drop spoonfuls of the remaining brownie mixture on top and swirl with a knife.

Sprinkle mini chocolate chips on top for added texture.

Bake in the preheated oven for 35 minutes or until set.

Allow to cool completely before cutting into squares.