Preheat your oven to 350°F and grease a loaf pan really well (I use butter and a light flour dusting so nothing sticks). Mix together 2 cups flour, 1 tsp baking powder, and 1/2 tsp salt in a small bowl and set aside. You don't want lumps of baking powder ruining your batter, so this dry mix prevents that totally.

In a large mixing bowl, cream together 3/4 cup softened butter and 1 1/2 cups sugar until it's light and fluffy, about 2-3 minutes with an electric mixer. It should look almost like frosting and feel lighter than when you started — this is crucial because you're incorporating air into the batter right now.

Add your 3 eggs one at a time, beating well after each addition so they fully combine. I learned the hard way that if you dump all three in at once, you'll get streaky batter that doesn't mix evenly. Takes maybe two extra minutes but seriously worth it.

Stir in 2 tsp lemon zest and pour in 1/2 cup fresh lemon juice while mixing on low speed — don't panic if the batter looks a little curdled for a second. It smooths out once you add your dry ingredients, I promise.

Alternate adding your flour mixture and 1/2 cup milk in three batches, starting and ending with flour. Mix on low speed after each addition just until combined — don't overmix or you'll toughen the crumb. This gentle approach is what keeps your cake tender and delicate.

Fold in 1 cup fresh blueberries gently with a spatula (I toss mine lightly in a little extra flour first so they don't sink to the bottom). Pour the batter into your prepared pan and smooth the top.

Bake for 55 minutes until a toothpick inserted in the center comes out with just a few moist crumbs. The top should be golden brown and springy when you gently press it. Let it cool in the pan for 10 minutes, then turn it out onto a wire rack to cool completely.