Step 1

Heat the oven to 325°F. Spray a loaf pan that’s about 8x5x3 inches with a nonstick coating.

Step 2

Whisk together the flour, baking powder, and salt until well blended. With an electric mixer (I use the paddle attachment on my stand mixer), beat the butter until it’s very pale and little tails have formed. Sprinkle in the sugar and beat well until slightly fluffy. Scrape the sides of the bowl well. Add the eggs one at a time, beating until blended before adding the next. With the mixer on low, add about one-third of the flour and mix until almost combined; then add half the buttermilk and mix until just combined. Repeat with another third of flour, and then the last half of the buttermilk, ending with the last third of the flour. Just before all the flour is incorporated, switch from the mixer to a stiff rubber spatula, add the lemon zest, and slowly stir to blend in the flour and zest, taking care to scrape the bowl’s bottom and sides.

Step 3

Scrape the batter into the prepared pan and bake until the cake is golden brown and a toothpick comes out with just a few crumbs clinging to it when inserted in the center, 45 to 50 minutes. Let the cake cool for about 10 minutes; as it’s cooling, stir together the lemon juice and confectioners’ sugar. Carefully invert the loaf pan, tap it to release the cake, and then brush the syrup on the cake while it’s still warm. Cool completely on a rack before serving.