Using a hand cranked food chopper or food processor on it's lowest chop setting, Individually chop whole jalapenos, onion and cilantro into small 1/8" pieces. Use all parts of the jalapenos, including seeds, for those wishing a milder version, remove all seeds.
Add this to a large tupperware bowl with a sealing cover.
Cut in half and core all tomatos, removing the flesh and seeds, discard corings. Leave only the "bowl" of the tomato. Hand cut these tomato halves into small 1/8" pieces, add all tomato to tupperware bowl with other ingredients.
Chop Mango into small 1/8" pieces, add to bowl.
Add Sea salt, and the juice of 4 limes.
Cover with sealing lid and shake vigorously until all ingredients are mixed evenly. Pop a small portion of the lid, invert over sink and carefully drain mixture of as much lime juice as possible, the dryer the mix the better. Chill.
Serve in serving dish or bowl and add tortilla chips or "scoops" to dip with.