Sardines Farcies aux Épinards

• 18 fresh sardines (heads, tails and backbones removed)
• 3 pounds fresh spinach
• olive oil

Wash spinach carefully and remove stems. Drain well and cook until limp. Place in a saucepan with 2 tablespoons olive oil, stirring constantly. Drain spinach and then chop finely with garlic.

Sauté finely chopped onion in 4