Sprinkle fish evenly with salt; place 1 fillet in each of 2 quart-sized microwavable zip-top plastic bags. Divide fennel and next 6 ingredients (through garlic) evenly between the 2 bags. Gently press out as much air as possible from bags; seal tightly.
Place bags on a microwave-safe plate. Microwave at POWER LEVEL 7 for 5 minutes or until desired degree of doneness. Cool 2 minutes.
Remove fish and vegetable mixture from each bag onto each of 2 plates. Top fillets evenly with orange sections and fennel fronds; drizzle with oil.