Melon and Avocado Crudo

Name: Melon and Avocado Crudo
Ingredients: 5 Tbsp. extra-virgin olive oil, divided; 1 garlic clove, finely grated; 1 1 piece ginger, scrubbed, finely grated; 2 oil-packed anchovy fillets; ½ tsp. crushed red pepper flakes; ¼ cup finely chopped cilantro, plus leaves for serving; 1 Tbsp. sherry vinegar or white wine vinegar; 1 lime; Kosher salt; ½ small honeydew melon, rind and seeds removed, cut into 3x1 pieces; 2 large avocados, cut into 2 pieces (about 6 pieces each); ½ small white onion, thinly sliced, plus more for serving; Handful fresh mint leaves (for serving; optional); Freshly ground black pepper; Flaky sea salt