Preheat broiler.
Place foil over a pie plate or small baking pan. Set aside.
Stem, seed, remove ribs, and cut red bell pepper into four pieces.
Place the cut side of the peppers face down on prepared baking sheet. Drizzle with 2 teaspoons of olive oil.
Broil under hot broiler until peppers are charred and fork tender, 8 to 10 minutes. To avoid burning, check after 5 minutes.
Dice charred pepper pieces into small pieces. Set aside.
Drizzle 2 teaspoons of olive oil into small pan. Add diced shallot and a pinch of salt. Over low-medium heat, stir constantly for 1-2 minutes or until shallot is tender.
Remove from heat. Stir in charred/chopped red bell pepper, seasoned rice vinegar, grated ginger, chopped mango and red pepper flakes (if using).
Serve immediately. Pairs well with burgers, fried fish, shrimp, roasted chicken.
Pour cooled salsa into small bowl and seal with airtight lid. Refrigerate until ready to use.