Prep the oven and pan: Move your oven rack to the lower third of the oven and preheat to 350°F (177°C). Lightly grease an 8×4-inch loaf pan with nonstick cooking spray. You can also use a 9×5-inch loaf pan, but your finished cake will be shorter.
Combine the dry ingredients: In a medium bowl, whisk together the all-purpose flour, baking powder, and salt. Set the mixture aside while you prepare the batter.
Cream the butter and sugar: Using a hand mixer or stand mixer, beat the softened butter on high speed for about 1 minute, until smooth and creamy. Add the sugar and continue beating for about 2 minutes, until the mixture is light and well combined. Scrape down the sides of the bowl as needed.
Cream the butter and sugar: Using a hand mixer or stand mixer, beat the softened butter on high speed for about 1 minute, until smooth and creamy. Add the sugar and continue beating for about 2 minutes, until the mixture is light and well combined. Scrape down the sides of the bowl as needed.
Finish the batter: Slowly add the flour mixture while mixing on low speed. Mix only until the ingredients are incorporated. Avoid overmixing. The batter will be very thick, which is exactly what you want for this pound cake.
Fill the pan and bake: Spoon the thick batter into your prepared loaf pan and smooth the top. For an 8×4-inch pan, bake for 55–65 minutes. If using a 9×5-inch pan, bake for 45–60 minutes. About halfway through baking, loosely cover the top with aluminum foil if it is browning too quickly.Since pound cakes are dense, baking times can vary from oven to oven. Start checking toward the shorter end of the baking range. The cake is ready when a toothpick inserted into the center comes out mostly clean. A few moist crumbs are perfectly fine. Cool the cake: Remove the loaf from the oven and place the pan on a wire rack. Let the cake cool in the pan for 1 hour. Carefully remove the warm cake from the pan and allow it to finish cooling on the rack or on a serving platter. You can drizzle on the icing while the cake is still slightly warm or wait until it has completely cooled.
Make the lemon icing: In a small bowl, whisk together the confectioners' sugar, fresh lemon juice, and heavy cream or milk until smooth. Pour the icing over the loaf, letting it naturally drip down the sides.
Serve: Slice and enjoy right away, or allow the cake to cool completely before slicing for cleaner, more defined pieces.
Keep the leftovers fresh: Cover the cake and store it at room temperature for up to 3 days, or keep it refrigerated for up to 1 week.
