Preheat oven to 350°F (180°C). Spray each well of Deluxe Mini-Muffin Pan with nonstick cooking spray. For cups, combine cake mix, allspice, egg and oil in Classic Batter Bowl; stir with Small Mix ‘N Scraper® until ingredients are moistened. (Mixture will be very thick.) Grate carrots using Ultimate Mandoline fitted with grating blade. Stir 3/4 cup (175 mL) of the carrots into batter; set aside remaining carrots for garnish. Using Adjustable Measuring Spoon, divide batter evenly among cups, filling cups about two-thirds full; bake 11-13 minutes or until cups feel firm to the touch.
Meanwhile, in clean Classic Batter Bowl, whisk together cream cheese and sugar until smooth; fold in whipped topping. Spoon cream cheese mixture into resealable plastic bag; secure bag and set aside.
Remove pan from oven to Stackable Cooling Rack. Press tops of cups with lightly floured Mini-Tart Shaper to make slight indentations. Cool in pan 3 minutes. Carefully remove cups from pan; cool 5 minutes. Trim corner of cream cheese-filled bag with Utility Knife; pipe filling evenly into cups. Garnish with chopped walnuts and reserved grated carrots, if desired.