6 ounces (168 grams) milk chocolate chips
3 ounces (84 grams) peppermint chips
1/2 cup (75 grams) whole wheat pastry flour
1/3 cup (37 grams) good quality dark cocoa powder
3/4 teaspoon (3 grams) kosher salt
1 stick (112 grams) butter, cut into pieces
1 1/2 teaspoons (7 ml) pure vanilla extract
3 large eggs (150 grams)
1 cup plus 2 tablespoons (225 grams) granulated natural cane sugar
Preheat the oven to 350ºF. Cut a piece of parchment paper large enough to cover the bottom and hang over the sides of a 1/4 sheet pan (9x13x1) baking pan.
Add the chocolate, peppermint chips, and butter to a medium, microwave-safe bowl. Cook on high power in the microwave in 30-second intervals, stirring in between each interval, until the chocolate and butter are melted. Be careful not to burn the chocolate. The timing depends on the wattage of your microwave. Stir in the vanilla extract; set aside to cool slightly.
In a small bowl, whisk together the flour, cocoa, and salt; set aside.
Add the eggs and sugar to a clean, large bowl. Whisk until they become thick and pale yellow, about 1 minute. Whisk in the melted chocolate mixture. Using a rubber spatula, fold in the flour mixture.
Pour the batter into the prepared pan, spreading it evenly to the sides. You can give the pan a tap on the counter to help it settle, too. Bake for 30 minutes until the center is set and the edges gently pull slightly away from the sides of the pan (the toothpick test does not work on brownies, so you just have to trust that they are done by visual cues). Let cool completely before cutting.