How To Make the Best, Easiest Blueberry Muffins

Name: How To Make the Best, Easiest Blueberry Muffins
Prep time: 20 min
Cook time: 28 min
Total time: 48 min
Cuisine: American
Ingredients: Cooking spray or paper muffin liners; 1/2 cup (1 stick) melted unsalted butter or canola oil; 3/4 cup granulated sugar; 2 large eggs; 1 teaspoon vanilla extract; 1 teaspoon finely grated lemon zest (from 1 lemon); 2 teaspoons baking powder; 1/4 teaspoon salt; 2 cups all-purpose flour, divided; 1 cup whole or 2% milk, divided; 1 1/2 cups fresh or frozen blueberries (about 6 1/2 ounces); 1/4 cup demerara or sanding sugar