Serve with chips or use to top grilled chicken or fish.
To prepare mango:
hold mango with a paper towel. Using a vegetable peeler, remove skin and discard. With a knife, slice off wide, flat part of fruit on both sides of the pit. Trim flesh from pit. Place parts cut side down, slice in half horizontally. Cut crosswise into thin strips; cut strips lengthwise into pieces.
To make guacamole:
In a medium bowl, combine avocados, mango, garlic, cilantro, lime juice, and serrano chile; season with ½ teaspoon salt. Fold gently, leaving texture chunky.