In a small saucepan, add lime juice, reserved juice from oranges and grapefruits, plus red pepper flakes, fresh ginger, garlic, honey and sesame seed oil. Cook over high heat and bring to a boil until thick. Remove from heat and let cool. Season to taste.
Place salmon fillets on a lined baking sheet, leaving space between them. Season with salt and pepper, then brush with some of the vinaigrette. Place in preheated oven and cook for eight to 10 minutes.
To a medium bowl add orange and grapefruit sections, grated red onion and cilantro. Gently fold together. Divide equally among four plates. Place a fillet of cooked salmon on each plate and drizzle all with the vinaigrette.
Per serving: 397 calories, 32 g protein, 19 g fat (3 g saturated fat), 27 g carbohydrates, 4 g fibre, 82 mg cholesterol, 71 mg sodium