Rub sugar with lemon zest in a large bowl until it is fragrant and takes on a yellow tint.

Sift in 2 cups of flour, baking powder and salt and whisk until evenly blended.

Combine eggs, yogurt, vanilla, oil, melted butter and milk in a medium bowl and whisk until completely smooth.

Pour the wet ingredients into the bowl with dry ingredients and gently fold it all together, then sprinkle remaining tablespoon of flour over the berries and toss to coat them, fold them into the batter.

Cover the bowl and set aside to stand for 30 minutes while the oven preheats.

Preheat the oven to 400°F and line a standard 12-cup muffin pan with paper liners.

Combine all streusel ingredients in a medium bowl and blend well until it resembles coarse crumbs.

Use an ice cream scoop or large spoon to divide the batter evenly among lined muffin cups, filling them right to the top. Cover each muffin with streusel topping.

Bake at 400°F for 10 minutes, then reduce the temperature to 350°F and bake for another 15 minutes until a skewer inserted into the center comes out clean.

Let muffins cool for 5 minutes in the pan and then transfer to a cooling rack.