Preheat your oven to 375°F (190°C) and line a muffin tin with paper liners or grease it well.
In a large bowl, whisk together the flour, sugar, baking powder, and salt until evenly combined. You’ll see a light, fluffy mixture that’s ready to hold the wet ingredients.
In a separate bowl, beat the eggs until slightly frothy. Pour in the melted butter and buttermilk, then add the lemon zest. Whisk until the mixture is smooth and combined well.
Gently pour the wet mixture into the dry ingredients, folding with a spatula just until you see no more streaks. Be careful not to overmix; a few lumps are okay, and this keeps the muffins tender.
Toss the blueberries with a small spoonful of flour, then gently fold them into the batter. This helps prevent sinking and ensures even distribution of berries.
Spoon the batter into the prepared muffin cups, filling each about 3/4 full. Sprinkle a tiny bit of raw sugar on top of each muffin for a crunchy, caramelized finish.
Bake in the oven for 20-25 minutes, or until the muffins are golden brown and a toothpick inserted into the center comes out clean. The kitchen will fill with a sweet, berry aroma as they bake.
Remove the muffins from the oven and let them cool in the tin for about 5 minutes. Then transfer them to a wire rack to cool slightly—this helps set the crumb and prevents sogginess.
Serve the muffins warm or at room temperature. They’re best enjoyed fresh, but will keep in an airtight container for up to 2 days. Reheat briefly in the oven to bring back that just-baked warmth and aroma.
