Preheat the oven to 190°C (gas 5). Grease and line the base of a 20cm sandwich tin.
Heat the oil in a deep heavy-based frying pan. Gently cook the onions for 5 minutes until transparent, then add the peppers and thyme. Add the garlic and cook for 20 minutes over a medium heat, stirring occasionally.
Add the olives and cheese to the vegetables, remove the thyme sprigs, if using fresh, and take the pan off the heat.
Season the beaten eggs with black pepper, then stir into the vegetables and mix well. Pour into the tin and bake for 35 minutes until golden and firm to the touch.
Remove cake from the oven and let it rest for 3 minutes. Turn it out onto a large plate, then flip it back onto a platter so it is right side up. Cut into wedges. It's delicious served hot, warm or cold.
If you have any leftover feta cheese, dice it finely with some stoned olives, drizzle with a little olive oil and chopped fresh herbs and use to fill hollowed-out cherry tomatoes. Serve as a nibble with drinks.
A few alterations - added one green pepper and mushrooms and used stirfry oil - didn't use olives or as much feta as the recipe called for. I didn't have thyme or garlic in so used worcester sauce and italian garlic spice and it tastes yummy! Will definitely use this recipe again! - 02 Feb 2015