Preheat oven to 350 F. Grease and lightly flour two 9x1 1/2-inch round baking pans, OR one 9x13-inch baking pan. Set pans aside.
In a large mixing bowl, stir together flour, sugar, Clabber Girl Baking Powder, baking soda, and cinnamon. Add cooking oil and eggs. Beat with an electric mixer on low to medium speed about 30 seconds or until combined. Stir in carrots. Spread batter in the prepared pans.
Bake in a 350 F oven for 30 to 35 minutes or until a toothpick inserted near the centers comes out clean. Cool in pans on racks for 10 minutes. Remove cakes from pans; completely cool on racks. Frost with Cream Cheese Frosting. Store in the refrigerator.
Cream Cheese Frosting:
In a large mixing bowl, using an electric mixer on medium to high speed, beat two 3-ounce packages cream cheese, 1/2 cup softened margarine or butter and 2 teaspoons vanilla until light and fluffy. Gradually add 2 cups powdered sugar, beating well. Gradually beat in 2-1/2 to 2-3/4 more cups powdered sugar until spreading consistency.
Carrot Cake with Pineapple:
Prepare as above, except stir in one 8 1/4-ounce can undrained crushed pineapple and 1/2 cup coconut with the shredded carrots. Bake about 40 minutes.
Carrot Cake with Raisins and Nuts:
Prepare as above, except stir in 1/2 cup raisins and 1/2 cup chopped walnuts with the shredded carrots.