Finely dice the red onion and mash the garlic clove until smooth.
Peel the mangoes and cut them into small, evenly sized cubes.
Peel the avocados and cut them into small cubes. Handle gently to help the avocado pieces maintain their shape.
Cut the cherry tomatoes in half.
Place the cubed mangoes, cubed avocados, halved cherry tomatoes, diced red onion, mashed garlic, and chopped cilantro in a large mixing bowl.
Squeeze the juice of 1 lemon over the ingredients.
Add the salt and olive oil.
Gently toss the salad until all ingredients are evenly combined and lightly coated with the lemon juice and olive oil.
Taste and adjust the salt, lemon juice, or olive oil as desired.
Serve immediately as a fresh salad, side dish, or topping for grilled meats, seafood, tacos, or rice bowls.