1 stick unsalted butter, cut into pieces and chilled
1 cup dark brown sugar
3/4 cup granulated sugar
2 large eggs, at room temperature
1 teaspoon vanilla extract
2 1/2 cups all-purpose flour
3/4 teaspoon baking soda
1/2 teaspoon kosher salt
1 cup semi-sweet chocolate chips
1 cup bittersweet chocolate chips
1/2 cup cooked, crumbled bacon
Preheat the oven to 350°F.
Beat the bacon fat, butter, and both sugars in the bowl of an electric mixer fit with a paddle attach-ment until pale and fluffy, about 4 minutes. Beat in 1 egg at a time until combined, then beat in the vanilla.
Stir together the flour, baking soda, and salt in a bowl, then beat into the batter on low speed until combined. Stir in the chocolate chips and crumbled bacon on low speed until combined.
Line 3 baking sheets with parchment paper. Using level 2 tablespoons of batter per cookie place balls of the batter on the baking sheets, leaving about 2 inches of space between each.
Bake the cookies until set and golden around the edges, about 12 minutes. Let cool completely.