Grilled-Fish Tacos

• 1 medium red onion
• 1/2 cup cider vinegar
• 1/4 cup sugar
• 7 tbls fresh lime juice, divided
• 1/4 cup chopped cilantro
• 1 tbls olive oil
• 1 1/4 lb mahimahi or tuna
• lime zest
• 2/3 cup mayo
• 2/3 cup sour cream
• 12 (6-inch) corn tortillas
• 6 to 8 radishes
• 1 to 2 (6- to 8-ounce) firm-ripe avocados
• 4 cups thinly slices green cabbage (1/2 small head)
• Accompaniment: lime wedges

1. Very thinly slice onion crosswise into rings. Heat vinegar, sugar, and 1/2 tsp salt in a small heavy nonreactive saucepan until sugar has dissolved. Remove from heat and stir in onion, then let stand until ready to use (about 25 minutes).
2. Meanwhile, stir 1/4 cup lime juice together with cilantro, oil, and 1/2 tsp salt. Add fish and toss to coat, then marinate at room temperature 15 minutes.
3. Whisk together mayo, sour cream, 1/2 tsp salt, and remaining 3 tbls lime juice to make sauce.
4. Preheat grill. Grill fish. Warm tortillas wrapped in foil on grill.
5. Slice radishes, and avocados.
6. Serve fish with tortillas, creme sauce, onions and remaining toppings.

red onion, cider vinegar, sugar, lime juice, cilantro, olive oil, mahimahi, lime zest, mayo, sour cream, corn tortillas, radishes, avocados, green cabbage, accompaniment

Taken from www.epicurious.com/recipes/member/views/grilled-fish-tacos-52376021 (may not work)