Avocado, Onion and Papaya Salsa

1 large avocado, pitted, peeled and diced
1 medium swet onion, chopped
1 ripe papaya (about 3/4 lb, 350 gr) peeled, seeded and diced
zest of lime, grated
1/4 cup (60 ml) fresh lime juice
1/4 cup (60 ml) rice vinegar
1/4 cup (60 ml) chopped cilantro (coriander leaves)
1 tsp (5 ml) sugar
1/2 tsp (2 ml) dried pepper flakes, or to taste
salt and ground pepper to taste

Combine all ingredients in a bowl and toss gently.  If preparing in advance, add the avocado at the last minute.  Makes about 3 cups (750 ml).