Prep the mangos: Peel, pit, and chop the mangos. You should have about 2 cups of chunks. If using frozen mango, thaw fully and drain any excess liquid.

Make the puree: Add mango, sugar, lime juice, vanilla, and a pinch of salt to a blender. Blend until completely smooth. Taste and adjust sugar or lime as needed. You want a bright, sweet-tart puree.

Optional—bloom the gelatin: If you prefer a firmer mousse that holds shape longer, sprinkle gelatin over 2 tablespoons cold water in a small bowl. Let it sit for 5 minutes to bloom.

Warm a portion of puree (if using gelatin): Transfer about 1/2 cup of the mango puree to a small saucepan and warm over low heat until just hot but not boiling. Remove from heat, add the bloomed gelatin, and stir until dissolved. Whisk this back into the remaining puree. Let the mixture cool to room temperature.

Whip the cream: In a clean, cold bowl, whip the heavy cream to soft peaks. It should hold shape but still look smooth and billowy. Do not overwhip.

Fold in the yogurt: Whisk the Greek yogurt in a separate bowl to loosen it. Gently fold it into the whipped cream until just combined.

Combine with mango: Add the cooled mango puree to the cream-yogurt mixture in two additions, folding gently with a spatula. Work slowly to keep the mixture airy. Stop as soon as it looks uniform.

Portion and chill: Spoon the mousse into serving glasses, ramekins, or a single bowl. Smooth the tops. Cover and chill for at least 2 to 3 hours, or until set. For the best texture, chill 4 hours or overnight.

Garnish and serve: Top with diced mango, a little lime zest, toasted coconut, pistachios, or a mint sprig. Serve cold.