In small saucepan stir together ancho pepper, lime juice, and water; cook on low heat, covered, for 10 minutes or until pepper is soft. Drain and cool. Remove pepper stem and seeds. Finely chop pepper; stir into softened butter or margarine. Slightly mash avocado with the salt. Stir into butter mixture. Store in refrigerator up to 1 week. Makes about 1/3 cup butter.