Preheat the oven to 400F.
Brown ground meat along with a little beer.
Add and saute garlic, onions, celery, and carrots with the beef.
Add tomato paste and cook a few minutes to get the raw tomato paste out.
Add herbs, fish sauce, Worcestershire sauce, and sprinkle with flour.
Add more beer and chicken stock. The liquid should thicken up from the flour.
Add peas, corn, and season to taste with salt and pepper.
Top with mashed potatoes (fresh or leftover) and dot with butter.
Bake for 40 minutes or until bubbly and golden brown on top.