Yield: 2 loaf cakes (or one bundt)

2 sticks (225 grams or 8 ounces) unsalted butter, at room temperature
2 1/2 cups (500 grams) sugar
4 extra-large eggs, at room temperature
1/3 cup grated lemon zest (6 to 8 large lemons)
3 cups (375 grams) all-purpose flour
1/2 teaspoon baking powder
1/2 teaspoon baking soda
1 teaspoon (5 grams) kosher salt
3/4 cup (175 ml) plus 3 1/2 tablespoons (50 ml) freshly squeezed lemon juice
3/4 cup (175 ml) buttermilk, at room temperature
1 teaspoon (5 ml) vanilla extract
2 cups (240 grams) confectioners’ sugar, sifted.

1. Heat oven to 350 degrees F (175 degrees C). Grease and flour two 8 1/2-by-4 1/4-by-2 1/2-inch loaf pans, and line the bottoms with parchment paper.

2. Cream butter and 2 cups sugar in the bowl of an electric mixer fitted with a paddle attachment for about 5 minutes, or until light and fluffy. Mixing at medium speed, add eggs, one at a time, and lemon zest.

3. Sift together flour, baking powder, baking soda and salt in a bowl. In another bowl, combine 1/4 cup lemon juice, buttermilk and vanilla. Add flour and buttermilk mixtures alternately to butter and sugar mixture, beginning and ending with flour. Divide batter evenly between pans, smooth tops, and bake for 45 minutes to 1 hour, until a cake tester comes out clean.

4. Combine 1/2 cup sugar with 1/2 cup lemon juice in a small saucepan, and cook over low heat until sugar dissolves.

5. When cakes are done, let them cool 10 minutes. Invert them onto a rack set over a tray, and spoon lemon syrup over cakes. Let cakes cool completely.

6. For glaze, combine confectioners’ sugar and remaining 3 1/2 tablespoons lemon juice in a bowl, mixing with a whisk until smooth. Pour over top of cakes, and allow glaze to drizzle down the sides.