apple cake recipe

- 2 cups (250 grams) all-purpose flour - 1 1/2 teaspoons baking powder - 1/2 teaspoon baking soda - 1/2 teaspoon salt - 1 teaspoon ground cinnamon - 1/2 teaspoon ground nutmeg - 1/2 teaspoon ground ginger - 1/2 cup (115 grams) unsalted butter, softened - 1 cup (200 grams) granulated sugar - 2 large eggs - 1 teaspoon vanilla extract - 1/2 cup (120 ml) buttermilk - 3 medium apples, peeled, cored, and chopped (about 2 cups) - 1/2 cup (60 grams) chopped walnuts or pecans (optional)