Step 1
Heat the oil in a 23cm pan with a lid and sauté the onion, carrot and celery for a couple of minutes until just beginning to soften. Stir in the rosemary with the beef cubes and sauté until golden on all sides.
Step 2
Add the Marmite, Worcestershire sauce, mustard and flour and cook for 1 minute, stirring. Pour in the stock and bring to a simmer, then cover and simmer gently for about 1 hour or until the beef is tender and the sauce has slightly reduced and thickened, stirring occasionally.
Step 3
Meanwhile, preheat the oven to 200°C/400°F/Gas Mark 6. To prepare the soufflé topping, place the cream, butter and Cheddar cheese in a small pan and melt over a low heat until runny – don’t worry if the mixture looks a bit curdled, as this is normal. Pour into a large bowl. Whisk the egg white until stiff and then fold into the melted cheese mixture. Season to taste and carefully fold in the bread cubes until evenly coated.
Step 4
Quickly spoon the soufflé topping on top the braised beef base and transfer to the oven for another 25-30 minutes or until the soufflé topping is golden brown and bubbling. Serve immediately with the buttered peas.