Preparation

1. Put onion slices into a medium bowl. Reserve.2. Put water, champagne vinegar, sugar and a pinch of salt into a small saucepan to boil. Once boiled, pour mixture over onion slices. Cool slightly, cover and refrigerate.3. While the onions are pickling, cook the fish: Put the fillets onto the tray inside the steamer. Secure lid.4. Select Seafood, set timer for 8 minutes and press Start. Once timer expires, check fish for doneness. Flesh should be opaque.5. Transfer cooked fish fillets to a serving plate. Sprinkle with ¼ teaspoon of the salt. Reserve.6. Wrap the tortillas in foil. Put the wrapped tortillas onto the tray inside the steamer. Secure lid. Select Manual, set the timer for 1 minute and press Start. Once timer expires, remove tortillas from steamer. Divide fish and avocado evenly among each tortilla. Sprinkle each with an even amount of the remaining salt and chili powder.7. Remove onions from refrigerator. Drain liquid and add desired amount of onions to each taco. Sprinkle each taco with a large pinch of the chopped cilantro and a squeeze of lime.