Step 1

Whisk the flour, baking powder, and salt in a bowl. Put 1 3/4 cups (218 g) of all-purpose flour into a mixing bowl and add 1 teaspoon (4 g) of baking powder along with 1/2 teaspoon (3 g) of baking soda and salt. Whisk for about 10 seconds so the dry ingredients combine.The baking soda and baking powder are important for helping the cake rise as it bakes. If you haven't baked in a while, check the expiration date on your baking powder and soda to ensure they're still good.

Step 2

Cream the butter and sugar in a separate bowl for 4 to 5 minutes. Get out a large mixing bowl and put 3/4 cup (170 g) of room-temperature butter into it along with 1 1/2 cups (300 g) of granulated sugar. Turn on a stand or hand mixer to medium speed and beat the mixture until it becomes light and fluffy.Tip: To cut back on the sugar, reduce the amount to 1 1/4 cups (250 g) of sugar. Keep in mind that the sugar will help the cake brown, so your reduced-sugar cake may be pale.It's important to use room-temperature butter, which will combine smoothly with the sugar. This will make your cake light and fluffy instead of dense.Stop the mixer and scrape down the sides of the bowl a few times to incorporate all of the butter.

Step 3

Beat 2 eggs into the butter-sugar mixture at low speed, 1 egg at a time. Turn the mixer down to low and add 1 room-temperature egg. Keep mixing until the egg is incorporated and then add the other egg. Continue to beat the mixture until you don't see any egg yolk or white.Beating in room-temperature eggs will trap air in the batter so your plain cake rises in the oven.

Step 4

Stir in the dry ingredients and buttermilk to make a smooth batter. Keep the mixer on low speed and stir in about 1/3 of the dry ingredients. Then, get out 3⁄4 cup (180 ml) of buttermilk or whole milk and pour 1/2 of it into the bowl. Once the liquid is incorporated, add another 1/3 of the dry ingredients. Finish making the batter by stirring in the remaining buttermilk followed by the rest of the dry ingredients.Stop stirring as soon as the last of the dry ingredients are mixed in. If you mix the batter too much, your cake can turn out tough or dense.