Step 1: Prepare the Muffin Batter Heat the oven to 350°F (175°C) and prepare a muffin tray by lining it with paper cups.In a large bowl, whisk together the dry ingredients: flour, baking powder, baking soda, salt, cinnamon, nutmeg, and cloves.In a separate bowl, mix the wet ingredients: pumpkin puree, both sugars, oil, eggs, and vanilla. Stir the wet and dry ingredients together until just combined without overmixing.
Step 2: Add the Cinnamon SwirlIn a small bowl, mix sugar and cinnamon.Fill each muffin liner halfway with batter, sprinkle a layer of cinnamon sugar, and then top with more batter. Use a toothpick to swirl the cinnamon sugar into the batter.
Step 3: Bake the Muffins Place in the oven and bake for 20–25 minutes, or until a skewer inserted in the middle comes out clean.Let the muffins cool in the tin for 5 minutes before transferring them to a wire rack.
Step 4: Add the GlazeMix powdered sugar, milk, and vanilla until smooth.Drizzle the glaze over the cooled muffins for a finishing touch.