Lebanese-style snapper

Name: Lebanese-style snapper
Prep time: 15 min
Cook time: 15 min
Total time: 30 min
Cuisine: Middle Eastern
Ingredients: 3 onions, 2 sliced into rings, 1 finely chopped; 110 ml olive oil; 1 garlic clove, crushed; 6 silverbeet leaves, stalks diced, leaves torn; 1½ tsp sumac; 4 baby snapper fillets (about 180gm each), skin on and pin-boned; To serve: coriander, flat-leaf parsley and thinly sliced Spanish onion dressed with a lemon vinaigrette; To serve: currants and toasted pine nuts; Tahini dressing; 2 tbsp tahini (unhulled or hulled, to your taste); Juice of 1 lemon; 2 tbsp olive oil