01 - Preheat oven to 350°F (175°C). Line a 12-cup muffin tin with paper liners or lightly grease each cup.
02 - In a large mixing bowl, whisk together mashed sweet potato, pumpkin purée, eggs, melted butter, whole milk, vanilla extract, and brown sugar until the mixture is smooth and homogeneous.
03 - In a separate bowl, whisk together all-purpose flour, baking powder, baking soda, salt, ground cinnamon, ground nutmeg, ground ginger, and ground cloves.
04 - Gradually add the dry mixture to the wet ingredients, stirring gently with a rubber spatula until just combined. Do not overmix; stop once no visible dry spots remain.
05 - Fold in the chocolate chips until evenly distributed throughout the batter.
06 - Divide the batter evenly among the prepared muffin cups, filling each approximately three-quarters full.
07 - Bake in the preheated oven for 20 to 22 minutes, or until a toothpick inserted into the center of a muffin emerges clean or with a few moist crumbs.
08 - Let muffins cool in the pan for 5 minutes before transferring to a wire cooling rack to cool completely.