Preheat your oven to 425. Butter an 8 x 8” baking pan and line with parchment paper or line with foil and butter or spray the foil with non-stick spray. Set aside.

Melt the chocolate and the butter together in a double boiler, or make your own double boiler by placing the chocolate and butter in a metal bowl and setting it over a pot of simmering water. Make sure the bowl is not resting in the water. Stir with a heatproof spatula until melted, take off the heat and set aside.

Whip the eggs, vanilla, optional kahlua, and sugar together in a stand mixer, or using hand held beaters. Beat it on high speed until thickened and pale, about 5-8 minutes.

Stir the melted chocolate into the butter mixture, then fold in the flour and salt.

Pour half of the batter into the pan, smoothing to the edges. Unwrap the peppermint candies and place in a single layer, 4 by 4 in the pan. Dollop the remaining batter on top and smooth the top.

Bake in the preheated oven until set in the middle, about 25 minutes. Remove to a cooling rack and let cool completely before slicing. Brownies keep at room temperature for 3 days, or frozen for up to a month.