Step 1

Preheat the oven to 350 degrees F. Lightly brush the inside of a 10x5 inch loaf pan with oil or nonstick spray, and line with a strip of parchment paper so that some is overhanging on the two long sides of the pan. Set aside.

Step 2

In a large bowl, mix together the lemon zest, lemon juice, vegetable oil, eggs, yogurt, sugar and vanilla with a whisk. Mix for about 1 minute until the mixture is very smooth and there are a few bubbles. Add the flours, salt, baking soda, baking powder and poppy seeds to the batter. Continue to whisk the mixture until just combined, and no more clumps of dry mix remain.

Step 3

Pour the batter into the prepared pan. Bake in the oven for 45 to 50 minutes, or until a toothpick inserted into the center of the loaf comes out clean. Allow the cake to cool in the pan for at least 30 minutes before transferring to a rack or plate to continue cooling.

Step 4

To make the glaze, add the powdered sugar and vanilla together to a small bowl. Add 1 tablespoon lemon juice, and mix in more as needed for a smooth texture. Drizzle the glaze back and forth over the cake. Slice and serve.