Preheat oven to 350°F. Grease the bottom of a 15x10x1-inch baking pan; line bottom of pan with waxed paper. Grease and lightly flour the waxed paper and the sides of the pan. Set aside.
In a large bowl, stir together flour, flax seed meal, baking powder, pumpkin pie spice, baking soda and salt; set aside. In another large bowl, combine finely shredded carrot, eggs, granulated sugar, brown sugar and oil. Add egg mixture all at once to flour mixture. Stir until combined. Spoon batter into prepared pan, spreading evenly.
Bake for 25 to 30 minutes or until a toothpick inserted near center comes out clean. Cool cake in pan on a wire rack for 10 minutes. Invert cake onto a wire rack. Cool completely.
In a medium bowl, beat cream cheese (Neufchatel) with an electric mixer on medium to high speed until smooth. Beat in vanilla. Gradually add powdered sugar, beating until smooth. Thaw frozen light whipped dessert topping. Fold about ½ cup of the topping into the cream cheese mixture to lighten. Fold in the remaining whipped topping.
Transfer cake to a large cutting board. Using a 2-inch round cutter, make cutouts in the cake, leaving as little space as possible between cutouts (see Tips). You should get 28 to 32 cutouts. For each serving, place one of the cake cutouts on a serving plate. Spread or pipe about 1 tablespoon Fluffy Cream Cheese Frosting atop the cake round. Top with a second cake round and about 1 tablespoon additional frosting. If desired, garnish with coarsely shredded carrot.
Tip: Be sure to finely shred the carrots to prevent them from sinking to the bottom of the pan during baking.
If desired, save cake scraps and make parfaits by layering the cake with thawed frozen light whipped dessert topping.
If using a sugar substitute, choose Splenda® Sugar Blend for Baking in place of granulated sugar. Choose Splenda® Brown Sugar Blend for Baking in place of brown sugar. Follow package directions to use product amount that's equivalent to ½ cup granulated and brown sugars. Nutrition analysis per serving: same as below except 231 calories, 25 g carbohydrates, 186 mg sodium. Daily values: 3% calcium. Exchanges: 1½ other carbohydrates. Carbohydrate choices: 1½