Step 1

Preheat oven to 350*F. Spray sides and bottom of pans with non-stick cooking spray. Line bottom of pans with parchment paper and spray the paper as well.

Step 2

Sift both flours, baking powder, baking soda and salt together in a medium bowl.

Step 3

Blend the sugar, eggs, lemon zest and lemon juice in the bowl of an electric mixer and mix until combined. Slowly add the melted butter, while mixing. Add sour cream and vanilla and mix until just combined. Use a rubber spatula to fold in the flour mixture, one third at a time, until all the flour is combined. Do not overmix.

Step 4

Divide the batter evenly between the prepared pans. Bake in the center of the oven for 20 minutes, rotate the pans, reduce the oven temperature to 325*F and bake another 30-35 minutes, or until toothpick inserted in the center of the loaf comes out clean. Let cool in the pans for 15 minutes.

Step 5

In a small saucepan over medium heat, heat the lemon juice and sugar until the sugar is completely dissolved. Once dissolved, continue to cook for 3 more minutes. Remove from heat and set aside.

Step 6

Line a half sheet pan with parchment paper and invert the baked and (mostly) cooled loaves onto the pan. Use a toothpick to poke holes in the tops and sides of the loaves.

Step 7

Brush the tops and sides of the loaves with the lemon syrup. Let the syrup soak into the cake and brush again. Let the cakes cool completely, at least 30 minutes.

Step 8

(The soaked, but unglazed loaves will keep well, wrapped in two layers of plastic wrap and frozen, for up to 6 weeks.)

Step 9

In a small bowl, whisk together the confectioners’ sugar and 4 tablespoons of lemon juice. The mixture should be thick but pourable. If the mixture is too stiff, add up to another 2 tablespoons lemon juice (a little at a time) and whisk again. Pour the glaze over the top of each loaf and let it drip down the sides. Let the lemon glaze harden, about 15 minutes, before serving.

Step 10

The glazed loaves will keep for up to 3 days, wrapped well in plastic wrap, at room temperature.