Preheat the oven to 180°C
Peel the sweet potato and cut into thin slices of ~5mm, place in an oven tray for 15 minutes
Slice the courgette and aubergine and place them in the baking tray with the garlic cloves and the sweet potato for an extra 15 to 20 minutes
In the meantime, chop the mint leaves and add into a small bowl together with the chopped tomatoes and spices
Grate the cheese and reserve
Once the vegetables are cooked and have soften, remove from the oven
Add the garlic cloves into the tomatoes mixture
In a baking dish, place one layer of sweet potato slices, then place a layer of courgettes and aubergines and cover with half of the tomato sauce and grated cheese. Repeat the process once more with the extra of baby spinach
Bake for around 30 minutes at 180ºC