Heat a 12-inch, deep skillet over medium high heat with olive oil and crushed red pepper. Add a chopped onion and sauté for about 5 minutes or until onion is softening. Add garlic and cook another minute. Season with a pinch each of kosher salt, pepper and thyme. Stir.
Add kale and let cook down, stirring occasionally, 2-3 minutes. Add grated lemon rind, the lemon juice, white wine, and season liberally with kosher salt and pepper.
Add salted and peppered salmon filets skin down. Reduce heat to low. Cover and steam about six minutes or until salmon is just barely firm, but still moist at center. Serve hot or at room temperature garnished with a sprig of thyme and/or cherry tomatoes.