There is a lot of confusion regarding what makes a green mango. Yes you can get the more common mango and eat them in their unripened stage, but they can be very, very sour, The mango we got is special because of its characteristics in its unripened stage, although I'm unsure of what exact species my mom got (as many varieties of special green mangoes exist). Even while unripened, specialized green mangoes are tart enough to be tart but not so sour that it makes your mouth pucker, and it has that wonderful crunchiness. As a note, if you leave the specialized green mango long enough, they do ripen to be sweeter, but usually not as sweet as the more common mangoes you'd find in a supermarket, and not as soft either. As least I've never left a green mango to ripen so much that it gets that soft or sweet- they're always eaten by then.
So getting back to how Vietnamese eat their green mangoes. We often dip it in a quick and easy sauce consisting of fish sauce, sugar, and hot chili peppers. The spicier for me, the better, but you can adjust it to your liking.
Recipe for the sauce:
2 tablespoons fish sauce
3 tablespoons sugar
2-3 thai chili peppers (or however many you'd like)
Mix this all together to create a thick syrup, and if you'd like it sweeter, add some more sugar.
I've actually tried regular sweet mangoes with this sauce out of desperation for a spice kick, and although not as good with green mango, it's still yummy.
I know there are lots of ways to eat mangoes as a snack, from sprinkling them with chili or drying the sweet version. How do you eat your mangoes, and do you prefer them sweet or tart?