Recipe from Martha's TV kitchen.
Peel eggs and cut in half, either lengthwise or crosswise. Carefully scoop out yolks, and arrange whites on a platter or tray.
In the bowl of a food processor, process egg yolks, avocado, lemon juice, and mayonnaise until smooth. Season with salt and pepper.
Transfer egg yolk mixture to a pastry bag fitted with a large star tip. Pipe mixture carefully and very neatly into egg halves. Cover with plastic wrap, and refrigerate until ready to use, up to 3 hours.