Preheat oven to 350°. Toss together first 3 ingredients; spread in a single layer in a foil- lined pan. Bake 10 minutes or until toasted, stirring once.
Stir together flour and next 4 ingredients. Beat butter and both sugars at medium speed with an electric mixer until blended. Add oil; beat until blended. Add eggs, 1 at a time, beating just until blended.
Add flour mixture to butter mixture alternately with buttermilk, beginning and ending with flour mixture. Stir in vanilla; fold in carrots, next 2 ingredients, and 1 cup toasted pecans. Spoon batter into 3 greased (with shortening) and floured 9-inch round cake pans.
Bake at 350° for 23 to 28 minutes or until a wooden pick inserted in center comes out clean. Cool in pans on wire racks 15 minutes. Remove from pans, and cool completely. Spread Brown Sugar-Cream Cheese Frosting between layers and on top and sides of cake. Top with Candied Carrot Curls and remaining toasted pecans.