Start by whisking together the lime, white vinegar, olive oil, sugar, salt, and black pepper for the salad dressing and set aside.
Then, cut the slightly under-ripe mango into thin strips and the red onion. Also, slice the tomatoes into half-inch slices.
First, arrange a layer of tomatoes on a large plate. Followed by placing the mango slices and red onion towards the middle.
Lastly, drizzle the salad dressing over everything and garnish with fresh cilantro and extra salt for taste.
Make sure to use slightly under ripe mangos, as this assures the mango strips are firm to eat and have a subtle sweetness that goes well with the tomatoes.