Scrub the sweet potatoes. Place one potato on a board between the handles of two wooden spoons, and carefully slice at just under ½cm intervals all the way along (the spoons will stop you going all the way through). Repeat with the rest of the potatoes.
Rub the potatoes with a small drizzle of olive oil and sprinkle with a tiny pinch of sea salt and black pepper. Roast on a baking tray for 45 minutes, or until cooked through and the skin is crisp.
A few minutes before your potatoes are ready, crush the pecans in a pestle & mortar, or bash in a clean tea towel with a rolling pin.
Carefully transfer the baked potatoes to serving plates, cut a cross in the top and gently break them open with a fork, mashing a little of the inside as you go.
Serve with a dollop of yoghurt, sprinkle over the pecans and drizzle with a little maple syrup – delicious!