Preheat the oven to 200°C, fan 180°C, gas 6. Heat the oil in a large pan, then add the onion, carrot and peppers, and cook for 10-15 minutes, until softened.
Put the cooked roast beef in a small bowl, add the flour and toss to coat. Add to the pan with the sun-dried tomato paste. Pour in the wine, tomatoes and beef stock and bring to a simmer. Let simmer for 15 minutes.
Meanwhile, put the ciabatta on a baking tray and heat in the oven for 8-10 minutes.
Stir the olives and chopped parsley into the stew. Divide between 4 bowls and serve with slices of warm ciabatta.