Wash the stew meat and remove from tendons. Tap dry and cover with flour all around. Cut the onions into not too thin slices, mince the garlic cloves.
Add butter or ghee to a frying pan and fry the meat chunks until browned. Add onion and garlic now. Let fry for 2 more minutes.
Now add the beer, beef stock, vinegar and all the spices in a spice bag, or a tea egg. Cover the pot and let it simmer on low heat 2 - 3 hours until the meat is tender. It is important not to cook on high temperature, medium to low temperature is just perfect.
Uncover the pot, add the mustard and place the slices of bread on top of the dish. Let it simmer until the desired thickness of the stew is reached. The bread will slowly dissolve and thicken the dish.
Remove the herbs. Add salt and pepper to taste and stir.
Serve with French Fries, short pasta or homebaked bread. The Flemish stew gets even better if you let it stand overnight, or a few hours minimum. This makes it really hearty.
Notes
To make it gluten free, just replace the flour with gluten free flour and do not use bread to thicken.