Heat olive oil in your Dutch oven.
Season beef cubes with salt and pepper.
Brown meat on all sides carefully.
Don't overcrowd the pan at all.
Remove beef and set aside temporarily.
Add onions to the same pot.
Cook until they're soft and golden.
Toss in carrots and garlic next.
Stir everything for two minutes.
Return beef to the pot now.
Add wine, broth, and tomato paste.
Drop in bay leaf and thyme.
Bring everything to a gentle boil.
Reduce heat to very low.
Cover and simmer for two hours.
The meat should become very tender.
Stir occasionally to prevent sticking.
Sauté mushrooms in butter separately.
Add them during the last minutes.
This keeps them from getting mushy.
Mix flour with a little water.
Stir it into the stew slowly.
Cook for five more minutes.