Pre Heat the oven to 180°C
Cut the sweet potatos about 2/3 deep - not through, you want to sort of fan it out without separating
Place in an oven proof dish, with the onions, garlic and thyme
Drizzle with half of the olive oil, making sure oil goes into the slices.
Roast for 30 minutes or until the sweet potatoes are cooked
Remove the sweet potato and set one side, and add the sausages to return to oven for 15 mnutes
Combine the balance of the oil with the jam, or honey (whatever you chose). Baste the sausages and if there is left over you can baste the potatoes and onions. I also sometimes add a splash of balsamic vinegar (if you using honey)
Roast for another 5 minutes
That should be it!