Preheat oven to 350°. Lightly coat a loaf pan with butter or oil. Dust with flour; tap out excess.
Whisk 1 1/2 cups flour, baking powder, and kosher salt in a medium bowl.
Using your fingers, rub sugar with lemon zest in a large bowl until sugar is moist. Add yogurt, oil, eggs, and vanilla extract; whisk to blend. Fold in dry ingredients just to blend.
Pour batter into prepared pan; smooth top. Bake until top of cake is golden brown and a tester inserted into center comes out clean, 50–55 minutes. (If the surface becomes darker than a golden brown while baking, cover the pan with foil and continue baking until cooked through.)
Let cake cool in pan on a wire rack for 15 minutes. Invert onto rack; let cool completely.
from Bon Appetit May 2012 (adapted only in that I doubled the lemon zest called for in the original...I felt it benefited from even more lemony kick).