Slice the aubergine lengthways and microwave on a plate for 4 minutes, or until soft in the middle (or bake in the oven for 40 minutes at 180 deg C).
Melt the coconut oil in a frying pan on a medium heat.
Finely chop the red onion and garlic and cook for a few minutes in the coconut oil until the onions are translucent.
Drain and rinse the beans in a colander under running water.
Add the beans, chopped tomatoes, tomato paste, paprika and chilli to the pan and cook for a few minutes.
Once the aubergine is cooked, top with the bean mix and cover with the cheddar. Melt the cheddar in the grill for a few minutes.
Serve on a bed of lettuce leaves.