Preheat oven to 350 degrees. Grease a 11x7 baking pan.
Cream together eggs, vanilla, pineapple, cinnamon, sugar and coconut. Sprinkle flour and baking soda over top and mix all together. Fold in walnut pieces.
Pour batter into pan and bake 30 minutes, or until toothpick comes out clean and edges of cake brown lightly. Cool and frost.
FROSTING: Mix 1 c. powdered sugar, 3 Tablespoons butter and enough lemon juice to make your desired consistency of frosting. You could replace the lemon juice with another liquid, but the flavor is a nice compliment to all of the tropical flavors.
GLUTEN FREE: Replace 2 c. whole wheat flour with 1 1/4 c. brown rice flour, 3/4 c. tapioca flour and 1 tsp. xanthum gum.