Preheat and prep. Heat your oven to 400°F (200°C). Line a 12-cup muffin pan with paper liners, or grease each cup well.

Make the crumble. In a small bowl, combine flour, brown sugar, granulated sugar, salt, and cinnamon. Add the cold butter cubes and rub with your fingertips until you get chunky crumbs. Refrigerate while you make the batter so it stays firm.

Mix dry ingredients. In a large bowl, whisk together 2 cups flour, sugar, baking powder, baking soda, and salt.

Mix wet ingredients. In another bowl, whisk yogurt, milk, oil, eggs, vanilla, and lemon zest until smooth.

Combine gently. Pour the wet mixture into the dry ingredients. Stir with a spatula just until most streaks of flour are gone. The batter should be thick and slightly lumpy—don’t overmix.

Prepare the blueberries. Toss blueberries with 1 tablespoon flour to help prevent sinking. If using frozen berries, do not thaw; toss quickly and work gently to avoid streaking.

Fold in berries. Fold blueberries into the batter with a few light strokes. Stop as soon as they’re evenly distributed.

Portion the batter. Divide the batter among the muffin cups, filling each about 3/4 full. For bakery-style domes, you can fill them a touch higher.

Add the crumble. Sprinkle a generous layer of chilled crumble over each muffin, pressing lightly so it adheres.

Bake hot, then reduce. Bake at 400°F (200°C) for 5 minutes to help the muffins rise tall. Without opening the oven, reduce the temperature to 350°F (175°C) and bake 14–17 more minutes, until the tops are golden and a toothpick comes out with a few moist crumbs.

Cool. Let muffins cool in the pan for 5 minutes, then transfer to a rack. Enjoy warm or at room temperature.