In a blender, place the lemon juice, garlic, ginger, cilantro, coriander seeds, turmeric, brown sugar, cumin seeds, mustard seeds and salt and puree.
Cook the onion in 1 tablespoon of the canola oil in a skillet until it is translucent (approximately 4 minutes). Add the pureed spices and cook an additional 3 minutes. Place mixture in a bowl and stir in the yogurt.
Preheat broiler. Rinse the fish and pat dry with paper towels. Slice fillets crosswise into 2 inch pieces.
Coat fish with half the yogurt mixture and dredge in breadcrumbs. Place the fish in a baking dish and drizzle with 1 tablespoon canola oil.
Broil fish 3 inches from the heat for about 3 minutes on each side. Set oven temperature to 450 degrees F and bake fish until it feels firm to the touch (approximately 10 minutes).