Fillet of Halibut with a Savory Tomato Sauce - Lidia

Ingredients

• 3/4 cup extra virgin olive oil
• 2 stalks of celery, diced
• 6 garlic cloves, peeled and crushed
• One 28-ounce can peeled Italian plum tomatoes, crushed lightly and passed through a food mill
• ½ cup loosely packed minced fresh Italian parsley leaves
• Salt and freshly ground black pepper to taste
• 1 ½ pounds fresh spinach leaves, tough stems removed, washed and drained
• Pinch peperoncino (crushed red pepper)
• Six 5- to 6- ounce pieces halibut fillet