Vanilla Bean Pound Cake

• 1 1/2 cups all-purpose flour
• 1 1/4 teaspoons baking powder
• 1 teaspoon kosher salt
• 2 sticks (8 ounces) unsalted butter, at room temperature
• 1 cup granulated sugar
• 2 vanilla beans, split lengthwise and scraped, seeds reserved (or 2 teaspoons vanilla extract)
• 4 large eggs, at room temperature

1. Heat the oven to 350°F and arrange the rack in the upper third. Butter and lightly flour a 9-by-5-by-3-inch loaf pan; set aside.
2. Combine flour, baking powder, and salt in a medium bowl. Whisk to aerate and break up any lumps; set aside.
3. Using an electric stand mixer fitted with the paddle attachment, beat butter at medium speed until creamy and smooth, about 1 minute. Add sugar and vanilla seeds and continue beating until light and fluffy, about 2 minutes more. (Stop the mixer periodically to scrape down the sides of the bowl.) Add eggs one at a time, beating well after each addition.
4. Reduce speed to low and add flour mixture in two additions, mixing each until just incorporated. (Do not overmix, or your cake will be tough.) Spread batter into the prepared pan and bake until the top of the cake is puffed and golden and a toothpick inserted into the center comes out clean, about 50 minutes. Transfer to a rack to cool for about 10 minutes. Run a knife around the perimeter, invert cake to remove from the pan, and let cool completely.