In a large mixing bowl, combine the sugar, flour, baking soda, salt, and cinnamon. Add drained pineapple, oil, eggs, and vanilla. Beat with an electric mixer until combined, scraping the sides of the bowl occasionally. Stir in bananas, applesauce, and walnuts. Divide batter between prepared pans.
Bake in a 350 degree F oven about 35 minutes or until top springs back when lightly touched. Cool cake layers on wire racks for 10 minutes. Remove from pans; cool thoroughly on wire racks.
Prepare the Cream Cheese Frosting; frost cake. Lightly press the 1-1/2 cups pecans into sides of cake. If you like, sprinkle the 2 tablespoons finely chopped pecans on top of cake. Cover and store in the refrigerator. Makes 12 to 16 servings.
Cream Cheese Frosting
In a large mixing bowl, cream cheese, butter and vanilla with electric mixer until light and fluffy. Gradually add powdered sugar, beating until smooth and of spreading consistency. Makes about 3-1/2 cups.