|Preheat oven to 190°and line a tray with well-oiled parchment paper. Slice each aubergine in half lengthwise and brush them generously, all over, with olive oil. Season with salt and place the halves, cut side down, on the prepared tray. Roast the aubergine until it is just starting to collapse and is tender when poked with a fork, about 25 minutes.
Meanwhile, heat 2 tablespoons of olive oil over medium-high heat. Add the leek and sauté until soft but not yet browned, 5–6 minutes. Add the pepper, cauliflower and garlic, and continue cooking 5–8 minutes more, until the vegetables are tender and fragrant. Remove the vegetable mixture from the heat and stir in the freshly grated tomatoes and herbs. Season to taste with mara pepper and salt.
When the aubergine is cool enough to handle, use a thin spatula to peel the halves gently away from the parchment. Flip them over and smother them with as much of the vegetable mixture as possible. Drizzle with the remaining 2 tablespoons of olive oil and return the pan to the oven for 10 minutes, or until the aubergine is hot and sizzles.
Carefully transfer the aubergines to a large platter and garnish with crumbled feta before serving.