Preheat oven to 180°C.
Grate the courgette and mince the garlic. Finely chop the spring onions
Lightly whisk the eggs then add the garlic, spring onion and courgette. Season with salt and pepper. Add the chilli flakes, if used.
Spray 4 silicon muffin baskets with cooking spray.
Line the sides and base of each muffin cup with a slice of prosciutto. Put a couple of basil leaves in each cup.
Divide the egg mixture between the muffin cups.
Cut the tomatoes in half, and put 3 halves on top of each muffin.
Bake for approx. 10 - 15 minutes, or until the egg has set.
Season with cracked black pepper, garnish with basil leaves and drizzle with balsamic glaze before serving.