Filet Mignon with Arugula Salad

Arugula, a tangy salad herb, will make a delicious addition to a tender, simply seasoned steak fried in a frying pan.
Preheat a large nonstick skillet over medium-high heat. Brush the mold with cooking spray. Sprinkle the beef with 1/4 teaspoon salt and 1/8 teaspoon pepper. Add the beef to the skillet; cook for 4 minutes on each side or until desired browning. Remove the beef from the pan; keep warm.Melt the butter in a skillet; brush the pan with cooking spray. Add the remaining 1/4 teaspoon salt, remaining 1/8 teaspoon pepper, red onion, and mushrooms to the pan; simmer for 4 minutes or until the mushrooms release liquid. Combine the juice and arugula in a large bowl. Add the mushroom mixture to the arugula mixture; mix gently. Place 1 1/2 cups salad mixture on each of the 4 plates; top each serving with 1 steak.