Heat 1 tbsp oil until very hot in a large, heavy based pot over high heat.
Pat beef dry with paper towels, then sprinkle with salt and pepper.
Brown beef aggressively in 2 or 3 batches, adding more oil if needed. Remove browned beef into a bowl.
If pot looks dry, add a touch more oil.
Add garlic and onion, cook for 2 minutes.
Add carrot and celery, cook for 2 minutes or until onion is translucent.
Stir in flour, then slowly pour in beef broth while constantly stirring.
Add beer, water, tomato paste, bay leaves and thyme, stir well. Then add the beef back in.
Cover, adjust heat to medium low so it’s bubbling gently. Simmer 1 hr 15 min or until beef is pretty tender.
Add potatoes and peas, simmer for a further 20 minutes without the lid. Add cooked mushrooms in the last 5 minutes.
The soup is ready when the potatoes are cooked and beef is very tender.
Adjust salt and pepper to taste.
Ladle into bowls. Sprinkle with parsley and serve with crusty bread if desired.
