Using ingredient button onions

Garlic Braised Tuna Steaks

• 4 tuna steaks
• 1 garlic clove
• 1 bay leaf
• 120 ml water
• 120 ml wine (red)
• 110 gr button onions
• 60 gr spinach
• 16 gr butter
• 6 gr tomato paste
• 3 gr flour