Put the mango nectar, tequila, and triple sec in a small pitcher. Add the lime juice, salt, and chili powder, and stir to combine.
If you’d like to add salt to the rim, place a little lime juice or water on a plate. Mix some flaky salt on another plate with a pinch of chili powder for color. Dip the rim of each glass in the lime juice or water and then into the chili salt. Add ice to each glass, and fill with margarita.