Goulash

1 onion,chopped
1 tbsp oil
1.5 tbsp smoked paprika
400g chopped tomatoes with chilli and peppers
500g cubed casserole beef
1 beef stock cube,dissolved in 100ml warm water
1 red pepper,sliced
1 green pepper,sliced
1 tbsp cornflour
Preheat oven to 150c/130c fan/gas 2.Cook the onions until soft,add the paprika,then add the tomatoes and heat until simmering.Pour into a oven proof dish and add the beef and stock.Cover and cook in the oven for 1 hour 50 min.Then add the peppers return to oven for 20 min.mix the cornflour with  cold water and add to the dish,cook for 10 min,and serve with mash potatoes.