Heat oven to 400°F. Cook rice as directed on package.

In a small saucepan, melt butter over medium heat. Sauté garlic and pepper flakes until garlic is lightly golden, 1 minute. Add syrup, juice and soy sauce; cook until bubbling, 3 minutes. In a bowl, combine cornstarch and 1 teaspoon water; stir into garlic glaze. Cook until slightly thick, 1 minute.

Arrange fillets on a foil-lined baking sheet. Spread 1 teaspoon glaze over each fillet. Roast until just cooked through, 12 minutes.

In a medium skillet, warm oil over medium heat. Add 1 package spinach; sauté until just wilted. Remove from pan; set aside. Repeat with second package spinach. Divide rice among 4 bowls; top each with 1/4 spinach and 1 salmon fillet, broken into large pieces. Drizzle with remaining sauce; sprinkle each with onions and sesame seeds