1. In a bowl, with a mixer on medium speed, beat butter and sugar until smooth. Add eggs, one at a time, beating well after each addition and scraping down sides of bowl as needed. Add pumpkin and vanilla and beat until well blended (mixture will look separated at this point).
2. In another bowl, mix flour, baking powder, cinnamon, nutmeg, cloves, and salt. Stir half the flour mixture into pumpkin mixture. Stir in milk just until blended. Add remaining flour mixture and stir just until incorporated. Spoon batter equally into 12 muffin cups (1/3-cup capacity; cups should be about 3/4 full) lined with paper baking cups.
3. Bake in a 350° regular or convection oven until tops spring back when lightly pressed in the center and a wooden skewer inserted into center comes out clean, about 20 minutes. Let cool in pans on racks for 5 minutes; remove cupcakes from pans and set on racks to cool completely, at least 30 minutes.
4. Spoon orange cream cheese frosting into a pastry bag fitted with a 3/4-inch star tip and pipe onto tops of cupcakes, or spread on cupcakes with a knife. Decorate with candy sprinkles, if desired.
Orange cream cheese frosting: In a bowl, with a mixer on low speed, beat 6 ounces cream cheese and 6 tablespoons butter, both at room temperature, until well blended. Beat in 1 1/2 cups powdered sugar, 1 tablespoon finely minced orange peel, and 1/4 to 1/2 teaspoon orange extract until smooth.
Nutritional analysis per cupcake.