Preheat the oven to 375ºF.
In a bowl, mix half the oil and the sweet potato. Season and place on a baking tray.
Roast the sweet potato for 25 minutes or until golden and soft.
While the sweet potato is roasting, fry the onion on a medium-low heat and add sugar to caramelize.
Once the sweet potato is roasted and the onion caramelized, assemble the bread. Cover the base with 1/3 of the cheese.
Next, add the sweet potato and the onion and cover with the remaining cheese and thyme.
Sprinkle with chopped thyme and flakes of ground pepper. Bake for 20-25 minutes or until the cheese has melted and the flatbread is toasted. Finish with freshly ground black pepper, slice and serve.