Deluxe macaroni cheese with grilled tomatoes recipe

INGREDIENTS

• 1 olive oil
• tbsp butter
• 25 onion, finely chopped
• g pancetta, chopped
• 1 flour
• 140 milk
• g crème fraiche
• 1 double cream
• tbsp Gruyère, grated
• 200 emmenthal, grated
• ml macaroni
• 3 tomatoes, cut into 5mm slices
• tbsp dried oregano
• 200 olive oil
• ml sea salt
• 50 freshly ground black pepper