1) Heat the oil in a saucepan over a medium heat. 2) Add the onions and carrots, and sauté for a few minutes to soften. 3) Add the thyme, Guinness, yeast extract and stock, bring to a simmer and cook for 10 minutes. 4) Meanwhile melt half of the spread in a frying pan and add the mushrooms and garlic. Fry for 5 minutes to brown. 6) Mix the cornflour with a little water to form a paste and add to the saucepan, stir to thicken. 7) Add the potatoes, black pepper and mushrooms to the saucepan and cook for a further 15 minutes or until the potatoes are cooked. 8) Just before serving remove the thyme stalk and stir in the remaining spread and allow to melt.