Kinilaw na Tuna (Ceviche with Ahi Tuna) - Filipino Chow

Ingredients

• 1 pound of tuna ahi filet, cut into cubes
• 2 thumb-sized pieces of ginger, minced
• 1 large red onion, minced
• 1 large cucumber, peeled then thinly sliced
• 6 " 7 pieces of red radish, peeled then thinly sliced
• 1 1/2 cup of vinegar
• 1/2 cup of calamansi juice
• 1 teaspoon of sugar
• 1 teaspoon of salt
• freshly ground black pepper to taste
• 1 " 2 pieces of red chilies, minced (optional)