Preheat the oven to 200°C.
Wash the sweet potatoes and cut them into slices without peeling them. Toss with 3 tbsp. of olive oil, rosemary, and thyme. Add salt and pepper to taste.
Place them in a casserole dish and let them cook for 20 minutes. Cut the figs into sections. After the sweet potatoes have cooked for 10 minutes, place the fig sections carefully between the sweet potatoes and cook everything until tender.
Remove the seeds from the chili pepper and cut it and the spring onions into rings. Pour the balsamic vinegar with the sugar into a saucepan. Bring to the boil and allow to reduce until the mixture becomes syrupy. Add the remaining tbsp. of olive oil, the red chili pepper and the spring onions and allow to simmer for a few minutes.
Remove the casserole from the oven. Sprinkle the whole casserole with the olive oil/spring onion/chili pepper mixture and drizzle the balsamic syrup over the figs.