1 1/2 cups all-purpose flour
1 teaspoon baking powder
1/2 teaspoon kosher salt
1/4 teaspoon baking soda
2 large eggs
1 teaspoon vanilla extract
10 tablespoons unsalted butter, room temperature
3/4 cup granulated sugar
3/4 cup (packed) light brown sugar
8 ounce mixture of chopped high-quality semisweet chocolate and white chocolate.
¾ cup chopped walnuts
Preheat oven to 375°F.
Whisk flour, baking powder, salt, and baking soda in a medium bowl. Lightly beat eggs and vanilla in a small bowl.
Using an electric mixer on medium speed, beat butter, granulated sugar, and brown sugar in a large bowl until light and fluffy, 3–4 minutes. Add egg mixture and beat, occasionally scraping down sides of bowl, until mixture is pale and fluffy, 3–4 minutes. Reduce mixer speed to low and gradually add dry ingredients, beating until just incorporated. Fold in chocolate and walnuts with a spatula.
Spoon about 12 heaping tablespoonfuls of dough onto each prepared sheet, spacing 1″ apart.
Bake cookies, rotating sheets halfway through, until just golden brown around the edges, 10–12 minutes (cookies will firm up as they cool). Transfer to wire racks and let cool completely.
I worked with this recipe.