1-First: preheat the oven to 425°F (220°C) and line a cupcake pan with paper liners to prevent sticking. Next, divide the blueberries by tossing 3/4 cup with 1 tablespoon flour; set aside the remaining 3/4 cup for topping to keep them from sinking.

2-Then, make the streusel by combining 2/3 cup all-purpose flour, 1/3 cup light brown sugar, and 1/4 teaspoon salt in a bowl, then add 1/4 cup melted unsalted butter and mix until coarse crumbs form.

3-Mixing and Baking Steps: 1. In a large bowl, whisk together 1 cup all-purpose flour, 1 teaspoon baking powder, and 1/4 teaspoon salt for the muffin batter. 2. In another bowl, whisk 1 large egg with 1/2 cup granulated sugar, then add 1/2 cup Greek yogurt, 1/4 cup vegetable oil, and 1/2 teaspoon vanilla; mix well. 3. Pour the wet ingredients into the dry ones and stir by hand just until combined, then gently fold in the floured blueberries (3/4 cup). 4. For the cream cheese filling, combine 6 ounces room-temperature cream cheese, 3 tablespoons granulated sugar, 1 teaspoon cornstarch, and 1 teaspoon vanilla; mix until just combined. 5. Assemble by spooning about 1 1/2 tablespoons batter into each liner, creating a well, then adding 1 tablespoon filling, and topping with more batter to fill cups two-thirds full. Add reserved blueberries and streusel on top. 6. Bake at 425°F for 5 minutes, then reduce to 350°F (175°C) and bake 22 to 25 minutes until golden. Cool in the pan for 5 to 10 minutes, then transfer to a rack. 7. Optionally, whisk 3/4 cup powdered sugar with 1 1/2 to 2 1/2 teaspoons milk or cream for a glaze and drizzle over cooled muffins.