Instructions

• Preheat the oven to 375°F. Generously spray a standard muffin pan with non-stick cooking spray and set aside.
• In a large bowl or the bowl of a stand mixer, add 1/2 cup softened unsalted butter and 2/3 cup granulated sugar. Cream together about 2 minutes, until smooth and well combined.
• Add 1 large egg and mix until incorporated. Add 1 1/2 teaspoons vanilla extract, 1/2 cup milk, and 1/4 cup plain Greek yogurt (or sour cream). Mix until just combined.
• In a separate bowl, stir together 1 2/3 cups all-purpose flour, 1 1/2 teaspoons baking powder, 1/4 teaspoon baking soda, 1/2 teaspoon ground cinnamon, and 1/2 teaspoon salt.
• Add the dry ingredients to the wet ingredients and fold or mix on low just until no large streaks of flour remain. Do not overmix.
• Divide the batter evenly among the prepared muffin cups, filling each about two-thirds full.
• Bake at 375°F for 15–20 minutes, or until a toothpick inserted into the center comes out clean or with just a few moist crumbs. Remove from the oven.
• While the muffins bake, melt 3 tablespoons butter. In a small bowl, combine 1/3 cup granulated sugar and 2 teaspoons ground cinnamon.
• Let the muffins cool in the pan for 1–2 minutes, then transfer them to a wire cooling rack. While the tops are still warm, brush each muffin top with the melted butter (or dip the tops in the melted butter), then immediately sprinkle or roll the tops in the cinnamon-sugar mixture to coat.
• Return the coated muffins to the wire rack and let cool until the topping sets before serving.