4 ounces unsalted American butter (about 1/2 cup; 113g), softened to about 65°F (18°C)
4 ounces light brown sugar (about 1/2 cup, firmly packed; 113g)
3 1/2 ounces white sugar, preferably well toasted (about 1/2 cup; 100g)
1/2 ounce vanilla extract (about 1 tablespoon; 15g)
2 teaspoons (8g) Diamond Crystal kosher salt; for table salt, use about half as much by volume or the same weight (plus more for sprinkling, if desired)
1 3/4 teaspoons baking powder
1 teaspoon baking soda
Pinch of grated nutmeg
2 large eggs (about 3 1/2 ounces; 100g), straight from the fridge
10 ounces all-purpose flour (about 2 1/4 cups, spooned; 283g), such as Gold Medal
15 ounces assorted chocolate chips (about 2 1/2 cups; 425g), not chopped chocolate; see note
8 1/2 ounces raw walnut pieces or lightly toasted pecan pieces (shy 1 3/4 cups; 240g)