Mackerel in Coconut Vinaigrette

Kinilaw na Tanguingue (Mackerel in Coconut Vinaigrette)
1 pound cubed Spanish mackerel fillet
1 cup white coconut vinegar
½ cup thick coconut milk
6 shallots, sliced
2 tablespoons chopped ginger
2 teaspoons sea salt
2 hot red or green pepper, sliced
dash of ground white peppercorns
shallot rings or sliced hot red pepper for garnish

• Marinate the fish cubes in half cup of the vinegar for 15 minutes. Drain well and discard vinegar.
  
• In a glass bowl, combine the remaining half cup of vinegar, coconut milk, fish, shallots, ginger, sliced hot peppers, salt, and ground white peppercorns. Cover with plastic wrap and chill in the refrigerator for 2 hours.
  
• Transfer into a serving plate and garnish with shallot and hot pepper.