1-First, start by preheating your oven to 375°F (190°C) and prepare your muffin tin by greasing it or lining it with paper cups for easy removal later. In a bowl, cream the butter with lemon zest and 1 cup of sugar until it becomes light and fluffy, which helps create those flavorful lemon blueberry muffins everyone loves.

2-Next, add the egg and vanilla extract, beating them in until fully combined for a smooth base. Now, toss the blueberries with ¼ cup of flour to keep them from sinking in the batter, ensuring even distribution in every bite.

3-Whisk together the remaining flour, baking powder, and salt in another bowl to mix the dry ingredients well. Alternate adding this flour mixture with the milk to the batter, stirring gently to combine without overmixing, then fold in the blueberries carefully.

4-Once your batter is ready, distribute it evenly into a jumbo or 12-cup muffin tin, filling each cup about two-thirds full and sprinkling the tops with the remaining tablespoon of sugar for a nice crusty finish. Bake for up to 30 minutes, depending on your tin size, until a toothpick comes out clean, and let the muffins cool in the pan for about 7 minutes before serving.