1/4 cup freshly squeezed lime juice (about 2 limes)
1 serrano chile minced (ribs and seeds removed for less heat, if desired)
2 ripe avocados pitted, peeled, and cut into 1/2-inch pieces
1 mango peeled, pitted, and cut into 1/4-inch pieces (below)
Hold mango with a paper towel (to avoid slippage). Using a vegetable peeler, remove skin and discard. With a knife, slice off wide, flat part of fruit on both sides of pit. Trim flesh from pit (discard pit) Place parts cut side down; slice in half horizontally. Cut crosswise into thin strips; cut strips lengthwise into pieces.
In a medium bowl, combine avocados, mango, garlic, cilantro, lime juice, and serrano chile; season with 1/2 teaspoon salt. Fold gently, leaving texture chunky.