Preheat the oven to 200ºC, fan 180ºC, gas mark 6. Using a metal spoon, scoop out the flesh of the aubergines, leaving a shell about 1cm-thick. Roughly chop the scooped out flesh and set aside.
Place the hollowed out aubergine 'boats' on a baking tray and brush lightly with half a tablespoon of the oil. Place in the oven and cook for 15 minutes, until just soft but still holding their shape.
Meanwhile, heat the remaining oil in a large saucepan and add the onion and the mince. Cook for 5 minutes, breaking up the mince, until browned. Add the chopped aubergine flesh and cook for a further 5 minutes.
Dissolve the stock cube in 100ml of boiling water and add to the mince, along with the tomatoes and mixed peppers. Season with freshly ground black pepper to taste. Simmer for 15 minutes, until all the liquid is absorbed and the mixture is thick.
Spoon the mince mixture into the baked aubergine boats and top with the cheese. Cook in the oven for 10 minutes.
Meanwhile, cook the rice according to pack directions. Serve the stuffed aubergines with rice on the side.
Make it veggie: Replace the beef mince with a pack of meat free mince, and simply cook as per the recipe above.