Turn it on to 350°F (175°C). While it’s heating up, get your cake pan ready—either grease and flour an 8-inch round pan or line it with parchment paper so the cake doesn’t stick.

Grab a medium bowl and mix together your flour, baking powder, and salt. Just stir them together with a whisk or fork. Set it aside for now.

In a bigger bowl, toss in the butter and sugar. Use a hand mixer or stand mixer and beat them until the mix looks fluffy and light—it should take about 3–4 minutes. Crack in the eggs one at a time, mixing each one in fully before adding the next. Then pour in the vanilla extract and mix it in.

Now add the sour cream (or yogurt) to the wet mixture and mix it in. After that, start adding the dry ingredients you mixed earlier, but do it a bit at a time, alternating with some milk. Start with the dry, then milk, and repeat—always end with dry. Mix just until it looks smooth. Don’t overdo it or the cake might turn out dense.

Pour the batter into your prepared cake pan. Use a spatula to even out the top. Slide it into the oven and bake for around 28 to 32 minutes. You’ll know it’s done when a toothpick poked in the center comes out clean. Let the cake sit in the pan for 10 minutes once it’s out, then carefully move it to a wire rack to cool off completely.

In a small bowl, stir together powdered sugar and 2 tablespoons of lemon juice. Then mix in some lemon zest, a bit of vanilla, and melted butter if you want a richer flavor. If it’s too thick, add a tiny bit more lemon juice. Too thin? Add more sugar.

Once your cake is fully cooled (seriously, wait or the icing will melt), drizzle or spread the lemon icing over the top. Let it sit for 10–15 minutes so the icing sets. Then slice and enjoy.