Step 1
Melt 2 table spoons of butter in a large skillet over high heat.
Add the beef cubes and sauté until nicely brown on all sides.
Season with salt & pepper.
Transfer the beef cubes to a casserole.
Step 2
Add the remaining butter to the skillet and melt over medium heat. Add the onions and cook them until brown, for about 10 minutes.
Add the onions to the meat in the oven.
Step 3
Deglaze the skillet with the beer and bring to a boil to loosen all the juices.
Pour the beer over the meat and add to the beef glace the thyme and bay leaves.
Step 4
Spread the slice of white bread with the mustard and put it on top of the stew in your pan.
Step 5
Let it simmer, uncovered, over low heat until the slice of bread with mustard falls apart. That is the sign that your beef stew is ready (about and hour to one hour and a half)
Step 6
Before serving, stir in the red-wine vinegar and the brown sugar. Let it simmer for another 5 minutes. Remove the bay leaves and the thyme. Taste and adjust the seasoning and serve.
Step 7
Serve with a Belgian beer

A nice “beef stew with beer” is a traditional Belgian dish. I love it and it still is one of the most popular dishes in Belgium. You can find it in Belgium in different varieties, because it is typically a dish that every mother cooks her own way.
Typically, use a dark, slightly bitter beer such as an abbey beer to cook it with. And like many stews, it is best made a couple of days ahead since it improves the flavor.
I serve the stew with fries and red cabbage, but you can easily serve it with a salad and cooked potatoes.
Bon Appétit! Eet Smakelijk!