Lemon Glazed Blueberry Muffins

1. Adjust oven rack to middle position and heat oven to 350 degrees. Spray muffin tin with nonstick vegetable cooking spray.

2. Whisk flour, baking powder, and salt in medium bowl until combined. Whisk egg in second medium bowl until well-combined and light-colored, about 20 seconds. Add sugar and whisk vigorously about 30 seconds; add melted butter in 2 or 3 steps, whisking to combine after each addition. Add sour cream in 2 steps, whisking just to combine.

3. Add frozen berries to dry ingredients and gently toss to combine. Add sour cream mixture and fold with rubber spatula until batter comes together and berries are evenly distributed, 25 to 30 seconds (small spots of flour may remain and batter will be thick). Do not overmix.

4. Use ice cream scoop or large spoon to drop batter into greased muffin tin. Bake until light golden brown and toothpick or skewer inserted into center of muffin comes out clean, 25 to 30 minutes, rotating pan from front to back halfway through baking time.

5. While muffins are baking, mix lemon zest and 1/2 cup sugar in small bowl. Bring lemon juice and 1/4 cup sugar to simmer in small saucepan over medium heat; simmer until mixture is thick and syrupy and reduced to about 4 tablespoons.

6. Remove muffins from oven onto wire rack, stand upright, and cool 5 minutes. After muffins have cooled, brush tops with glaze, then, working one at a time, dip tops of muffins in lemon-sugar. Set muffins upright on wire rack; serve.