Prep the oven and pan: Heat to 425°F (220°C). Line a 12-cup muffin tin with paper liners or grease well.
Mix dry ingredients: In a large bowl, whisk flour, sugar, baking powder, baking soda, and salt.
Reserve 1 tablespoon of this mixture to toss with the blueberries.
Flavor boost: Add lemon zest to the dry mixture. Rub it in with your fingers to release the oils for stronger lemon aroma.
Combine wet ingredients: In a separate bowl, whisk eggs, yogurt, milk, oil, melted butter, vanilla, and lemon juice until smooth.
Fold together: Pour wet into dry. Stir with a spatula until just combined.
A few small streaks of flour are fine. Do not overmix.
Prep blueberries: Toss blueberries with the reserved tablespoon of flour. Gently fold into the batter. If using frozen berries, add straight from the freezer.
Portion: Divide batter evenly among the cups, filling them almost to the top for a tall dome.
Sprinkle with coarse sugar if you like a crunchy top.
Bake high, then lower: Bake 5–6 minutes at 425°F (220°C), then reduce to 350°F (175°C) without opening the door. Bake another 12–15 minutes until the tops are golden and a toothpick comes out mostly clean.
Cool: Let muffins cool in the pan for 5 minutes, then transfer to a rack to finish cooling. This prevents soggy bottoms and keeps the crumb tender.
Optional glaze: For extra zing, whisk 1/2 cup powdered sugar with 1–2 tablespoons lemon juice and drizzle over cooled muffins.