Great Greek Halibut

4 halibut fillets, about 6 - 8 ounces each
olive oil, lemon juice, salt and pepper
1 cup red onion, thinly sliced
2/3 cup pitted kalamata olives, chopped
1 1/2 cup fresh basil leaves, loosely packed
2 teaspoon Dijon mustard
4 - 5 tablespoons balsamic vinegar
3 - 4 garlic cloves, thinly sliced
1 1/2 cups diced tomato
4 - 5 handfuls fresh spinach leaves
1/2 cup crumbled feta cheese


Instructions:
Rub fish with olive oil and lemon juice. Season with salt and pepper. Heat a couple of tablespoons of olive oil in a large skillet over medium-high heat. Add fish and brown on one side, about 4 minutes. Flip over and cook for about 2 minutes more, or until fish is barely done (Remove fish from skillet before overcooking and cover - fish will cook up a bit when covered.  If already done -- don‘t cover).  To skillet, add onion and next 5 ingredients, cook for 2 minutes.  Next add spinach, tomato and a tablespoon or more olive oil (if needed).  Heat until spinach starts to wilt.

Mound spinach mixture on center of plates. Top with fish. Sprinkle feta cheese on top.