Heat oven to 200C/180C fan/gas 6. Pierce the sweet potatoes a few times with a fork, then cook them in the microwave on High for 8 mins or until soft. Rub with 1 tsp of the paprika, 1 tsp of the oil and some seasoning. Transfer to a baking tray, put in the oven and cook for 10-15 mins until crispy.Meanwhile, make the beans. Cook the onion in the remaining oil until soft. Add the garlic, sugar, vinegar, Worcestershire sauce and the remaining paprika, and cook for a further 1-2 mins until sticky. Tip in the beans, tomatoes and a splash of water, and simmer until the sweet potatoes are ready.Serve the sweet potatoes with the beans on top, a dollop of soured cream and a pinch of paprika, if you like.