Venison Stew

2 sticks celery, cut into chunks 
1 onion, chopped 
3 carrots, chopped into large chunks 
5 bay leaves 
3/4 tsp thyme 
1 Tbsp vegetable oil 
1 Tbsp butter

2 Tbsp plain flour 
2 TBsp tomato purée 
2 TBsp Worcestershire sauce 
2 beef stock cubes, crushed 
1 lb venison, cubed 

Heat the oven to 320. 
 Put the celery, onion, carrots, bay leaves and thyme in a large Dutch oven with the oil and butter. Cook the vegetables gently for about 10 mins. Then add the flour and mix together until the flour has been absorbed by the vegetables. 
Add the tomato purée, Worcestershire sauce and beef stock cubes.
 Add 2-1/4 cups boiling water, and stir so that the stock cubes begin to dissolve. Add the venison and bring to a simmer. 
Cover and cook for 2hrs 30 minutes, then uncover and cook for an additional 30 minutes or so, until the meat is extremely tender and the sauce has begun to thicken.