Preheat oven 350.
Prepare 9 x 13 pan with non stick spray.
Sift together:
flour, soda, cinnamon and salt. Set aside.

In separate bowl with hand or stand mixer, beat sugar, oil, eggs and vanilla until thoroughly mixed.
Gradually mix in flour mixture until completely blended.
Fold in carrots, pineapple and nuts.
Pour into prepared 9 x 13 pan. Bake @ 350 for approx. an hour, or until toothpick comes out clean. Cool completely. Frost.

Frosting:
With hand or stand mixer, beat together, 1/2 c. butter, 8 oz. cream cheese, 2 c. powdered sugar and 1 tsp. vanilla.
Frost cake only when completely cool.
Store cake in the refrigerator.