Preheat the oven to 425° and place muffin liners in a muffin pan. Spray with nonstick cooking spray.
Combine the flour, baking powder, baking soda, cinnamon, nutmeg, and salt in a mixing bowl.
2 cups all-purpose flour, 1 and ½ teaspoon baking powder, ½ teaspoon baking soda, ½ teaspoon ground cinnamon, 1 teaspoon freshly grated nutmeg, ½ teaspoon salt
In a large bowl, cream the butter, sugar, and brown sugar till creamy.
½ cup butter, ⅓ cup granulated sugar, ½ cup brown sugar
Add the eggs and beat for another 30 seconds.
2 large eggs
Beat in the milk, sour cream, and vanilla until combined.
¼ cup whole milk, ½ cup sour cream, 1 teaspoon pure vanilla extract
Mix in the dry ingredients to the wet ingredients just till combined.
Do not overmix or the muffins can become dense.
Fill the cupcake liners even with the top.
Place in the oven and bake for 5 minutes. After 5 minutes, reduce the heat to 350° and continue baking for 15 minutes till a toothpick inserted comes out clean.
Combine the sugar and cinnamon together in a small bowl.
½ cup granulated sugar, 2 teaspoons ground cinnamon
Brush one of the muffins with melted butter, then roll in the cinnamon sugar. Repeat until all the muffins have been rolled in the cinnamon sugar.
5 tablespoons butter
Fill a piping bag with a large circle tip, with the cajeta, then press the tip into the center of the muffin and pipe the cajeta into the muffins. Or, drizzle the cajeta over the tops.
Dulce de leche
Serve with coffee or milk for a delicious snack.
Notes
Store in an airtight container in the refrigerator for up to 5 days.