Preheat oven to 350°F. Line muffin pan with baking cups.
Puree avocado in food processor until smooth. In large mixing bowl, combine cake mix, pudding mix, eggs, water, avocado puree, oil, juices and zest; beat on low speed until combined. Beat on medium speed 2 minutes. Spoon into prepared pan, filling cups 3/4 full.
Bake 18-20 minutes or until a wooden pick inserted in center comes out clean. Cool completely before decorating.
Makes about 24 cupcakes.