I made this lemon-lime yogurt cake on a whim a few years ago because I wanted to try substituting butter. Very quickly it became a favorite! It's super moist and has a different texture from usual pound cakes. Sometimes I make it all lemon and also add half sour cream, which makes it even better.
Spray or butter a 10x4-inch (27x9cm) loaf cake pan and line it with a strip of parchment paper, covering the bottom and two short sides. The long sides will be greased but not lined.
In a large bowl beat sugar, yogurt, sour cream, oil, eggs, half the lemon and lime juices, zest, and vanilla for 1-2 minutes.
Add dry, sifted ingredients (flour, baking powder, and salt) in 2 parts and beat just to incorporate well. Don't overbeat or the cake will be tough.
Pour batter into the prepared pan and bake for 45-50 minutes, until a toothpick inserted comes out clean. The surface will be shiny and possibly cracked, not as dry as regular cakes.
Let cool on a wire rack.
To remove the cake from the pan, run a smooth-bladed knife along the sides to unstuck any parts. Carefully lift the cake, helping yourself by lifting the parchment paper.
For the citrus glaze:
Beat powdered sugar with remaining citrus juice until no lumps remain. Add juice in batches so you make it as thick or runny as you wish.
Pour over room temperature cake and decorate with zest before it hardens.
Notes
Baking time: Consider that all ovens and pans are different, even if they look similar. The baking time in my recipes is as accurate as possible, but it might take you more or less time. You can use a thermometer to check that your oven is at the right temperature. I recommend keeping track of how your oven works and what tiny details you might need to adjust. Yogurt: I found that different brands make a slight difference in the cake's texture, so you might need to find the one you like the most. I don't recommend using low-fat yogurts.Storing: this loaf cake keeps very well for a few days. I recommend covering it in plastic wrap so it doesn't dry out. It can be frozen up to a month.