Blueberry Muffins

INGREDIENTS

Lemon-Sugar Topping:
• 1/3 cup sugar
• zest from one lemon
Muffins:
• 2 cups frozen blueberries (or 2 cups fresh)
• 1 1/8 cups (8 ounces) plus 1 teaspoon sugar
• 2 1/2 cups (12 1/2 ounces) all-purpose flour
• 2 1/2 teaspoons baking powder
• 1 teaspoon salt
• 2 large eggs
• 4 tablespoons butter, melted and cooled slightly
• 1/4 cup oil (vegetable or canola)
• 1 cup buttermilk
• 1 1/2 teaspoons vanilla extract

DIRECTIONS

1. For the topping, stir together sugar and lemon zest in a small bowl and set aside.
2. For the muffins, adjust an oven rack to the middle position and preheat oven to 375 degrees. Spray a standard muffin tin with nonstick cooking spray. Rinse one cup frozen berries under cold water and spread on a double layer of paper towels to dry well. Bring remaining one cup berries and 1 teaspoon sugar to simmer in a small saucepan over medium heat. Cook, mashing berries with a spoon several times and stirring frequently, until the berries have broken down and the mixture is thickened and reduced to about 1/3 cup, about 6-8 minutes. Transfer to a small bowl and cool to room temperature, about 10 to 15 minutes.
3. Whisk the flour, baking powder, and salt together in a large bowl. Toss the berries that have dried on the paper towels in with the flour mixture. Whisk remaining 1 1/8 cups sugar and eggs together in a medium bowl until thick, about 45 seconds. Slowly whisk in the butter and oil until combined. Whisk in the buttermilk and vanilla until combined. Using a rubber spatula, fold egg mixture into flour mixture until just moistened. The batter will be lumpy with a few dry spots of flour – don’t overmix. This is the key to moist and tender muffins.
4. Using ice cream scoop or large spoon, fill the muffin cups until they are about 3/4 full. Spoon a teaspoon of cooked berry mixture into the center of each mound of batter. Using a skewer (or a chopstick), gently swirl the berry filling into the batter using a figure eight motion. Sprinkle lemon sugar evenly over the muffins.
5. Bake until the top of the muffins are golden and just firm, 17-18 minutes. Cool muffins in the muffin tin for 5 minutes, then transfer to a wire rack and cool 5 minutes before serving.