Chocolate Hazelnut Cookies

Name: Chocolate Hazelnut Cookies
Ingredients: 3 cups (15 ounces) all purpose flour; 1 teaspoon baking powder; 1 1/2 teaspoons baking soda; 1 1/2 teaspoons kosher salt; 2 1/2 sticks (10 ounces) unsalted butter; 1 1/2 cups (about 10 ounces) light or dark brown sugar; 1 cup (about 7 ounces) granulated sugar; 2 large eggs; 1 teaspoon vanilla extract; 2 (4 ounce) bars bittersweet chocolate, 60% cacao, still in their package; 2 (4 ounce) bars dark chocolate, 80 to 100% cacao, still in their package; 1 1/2 cups (about 6 ounces) toasted hazelnuts, peeled and roughly crushed under a skillet or in a mortar and pestle; Flaky sea salt such as fleur de sel or maldon