Preheat your oven to 180 degrees celsius. 

1. Roast the aubergine and pepper: Toss the aubergine and pepper slices with 1 tablespoon of olive oil and a good pinch of salt and pepper. Layer the aubergine and pepper in a single layer onto a baking tray (you may need more than one tray) then roast them in the oven for 35-40 minutes, turning halfway, until tender and have taken on some colour.
2. To make the harissa tomato sauce: begin by heating the remaining tablespoon of oil in a saucepan on a medium heat. Saute the onion for 5-7 minutes until it has softened, then add the garlic and cook for a further 2 minutes. Add the tinned tomatoes, harissa paste, red wine vinegar and sugar to the saucepan and stir everything to combine. Simmer the sauce for approximately 20 minutes, until it has thickened up.
3. Remove the roasted pepper and roasted aubergine from the oven and gather the sauce, feta and breadcrumbs together to begin layering it all up!
4. Layer it up: In a 12-inch baking dish layer half the aubergine in the bottom of the tray, then layer half the roasted pepper on top of that. Spread half the tomato sauce on the pepper before repeating the aubergine, pepper and sauce layer.
5. Top the bake with the crumbled feta cheese and sprinkle on the breadcrumbs.
6. Bake it: Cook the pepper, aubergine and feta bake in the oven for approximately 30 minutes until the top is golden brown and crunchy. Serve and enjoy!