01 - Preheat oven to 350°F. Line a 12-cup muffin tin with paper liners or lightly grease each cup.
02 - In a large bowl, whisk together whole wheat flour, baking powder, baking soda, salt, cinnamon, ginger, nutmeg, and cloves until evenly mixed.
03 - In a separate bowl, whisk pumpkin puree, oil, brown sugar, granulated sugar, eggs, vanilla extract, and milk until smooth.
04 - Pour wet mixture into the dry ingredients and gently stir just until incorporated. Avoid overmixing to maintain tenderness.
05 - Spoon batter evenly into muffin cups, filling each approximately three-quarters full.
06 - Place tin in the oven and bake for 20 to 22 minutes, or until a toothpick inserted in the center of a muffin emerges clean.
07 - Allow muffins to cool in the tin for 5 minutes. Transfer to a wire rack and let cool completely before decorating.
08 - Use melted chocolate piped from a bag or a toothpick, or place mini chocolate chips, to create jack-o'-lantern faces atop the cooled muffins. Add green candies or pumpkin seeds as stems if desired.