Preheat your oven to 200°C (400°F). In a bowl, toss the cubed eggplant with 1 tablespoon of olive oil, the balsamic vinegar, and a pinch of salt. Spread the eggplant across a baking sheet in a single layer and roast for 30 minutes until tender and slightly browned. Remove and let cool.

Heat the remaining tablespoon of olive oil in a skillet over medium heat. Add the sliced onion and cook for 2–3 minutes until softened and translucent. Stir in the minced garlic and cook for just 1 minute more until fragrant, then remove from the heat and mix with the roasted eggplant.

In a medium bowl, whisk together the eggs and double cream until completely smooth. Stir in most of the shredded cheese (reserve a small handful for the top), the chopped herbs, salt, and pepper.

Thoroughly grease a 28cm (11-inch) scalloped quiche or pie dish with butter or oil spray. Evenly spread the cooled eggplant, onion, and garlic mixture across the bottom of the dish. Pour the egg and cheese custard slowly over the vegetables. Arrange the thick tomato slices across the top of the mixture, pressing down gently into the egg mixture. Scatter the remaining cheese and a few extra fresh herbs over the tomatoes.

Bake in the oven for 25–30 minutes until the egg mixture is completely set in the center and the cheese is golden and bubbling.

Remove from the oven and let it rest in the dish for 10 minutes before slicing. This allows the custard to firm up so it cuts cleanly. Serve warm or chilled alongside a fresh side salad!