Cold Eggplant Provencale

• 2 onions
• 2 garlic (cloves)
• 2 celery hearts
• 240 ml olive oil
• 26 gr parsley (chopped)
• 5 gr currants
• 3 gr peppercorns
• 3 gr capers
• 1 gr basil
• 6 slices tomatoes