2 large red onions, thinly sliced
1 1/2 cups sour orange juice or 1 cup orange juice and 1/2 cup lime juice
1 tablespoon sugar
1 teaspoon salt
1.Cover the red onion slices in boiling water for 10 seconds and drain.
2.Mix the juice, sugar and salt, pour the mixture over the red onions and let sit, covered, for 4 hours.