Pan Seared Wild Salmon with Mustard-Caper Butter and Wilted Spinach

For salmon:

Preheat oven to 425 degrees. Rub both sides of salmon fillets with olive oil and season tops very liberally with salt and pepper. Heat a dry ovenproof sauté pan over high heat for 2-3 minutes. When the pan is very hot, lower heat to medium and place the salmon fillets seasoning-sides down in the pan and cook without moving them for 2 minutes, until very browned. Turn the fillets and place the pan in the oven for 3 to 5 minutes, until the salmon is cooked rare.

For spinach:

While salmon is in the oven, heat oil in a large skillet over medium heat. Add red onions, cook, stirring, 1 to 2 minutes. Raise heat to medium-high. Add half the spinach, and cook, stirring until wilted, about 2 minutes. Add remaining spinach, and cook until wilted, about 2 minutes more. Stir in salt, pepper, and lemon juice.

For mustard-caper butter:

Combine all ingredients in a small bowl and stir to blend. Cover with plastic wrap and refrigerate until ready to serve.

To serve, place spinach in center of plate and top with salmon fillet. Spread some mustard-caper butter on salmon and garnish with lemon slices. Serve immediately.