Yields: 16 squares or 32 bars.
For the bars:
¾ cup unsalted butter
½ cup packed brown sugar
½ cup granulated sugar
2 eggs
1 teaspoon vanilla
1¾ cups all-purpose flour
1½ teaspoons baking powder
2 cups zucchini, shredded
1 cup sweetened coconut flakes
¾ cup walnuts, chopped
For the cinnamon frosting:
1 cup powdered sugar
1½ tablespoons unsalted butter, melted
½ teaspoon cinnamon
2½ tablespoons milk
1 teaspoon vanilla
1 teaspoon fresh lemon juice
For the bars: Preheat oven to 350°. Prepare a 15 x 10 x 1½-inch-deep baking pan with shortening.
In a medium-size bowl, cream butter until light and fluffy. Beat in brown and granulated sugars gradually, then add eggs one at a time. Add vanilla and mix well. Slowly add flour and baking powder.
Stir in zucchini, coconut, and walnuts. Spread zucchini mixture evenly into prepared baking pan. Bake for 40 minutes or until a toothpick inserted in the center comes out clean. Remove from oven and place on cooling rack. Let sit until completely cooled. Spread frosting evenly over cake. Cut into bars or squares. Store in an airtight container in refrigerator.
For the frosting: Using an electric mixer or a food processor, mix all ingredients together until smooth. Depending on personal preference for consistency, you may add more sugar or milk.