In a large bowl, combine the boneless beef chuck with dry red wine, pearl onions, carrots, garlic, fresh thyme, and bay leaves. Cover and refrigerate for 12 to 24 hours.

Once marinated, strain the marinade, reserving the wine. Pat the beef dry, season with salt and black pepper.

In a large Dutch oven, heat olive oil and sear the beef on all sides for about 6–8 minutes. Remove and set aside.

In the same pot, sauté mushrooms for 5-7 minutes until browned. Set aside.

Add pearl onions back into the pot and sauté until golden. Add garlic and cook for another minute.

Pour in reserved wine, bring to boil, reduce heat and simmer until reduced by half, about 15-20 minutes.

Lower heat, add butter, carrots, tomato paste, and flour to form a roux. Gradually whisk in beef stock.

Return seared beef to the pot, pour in the reduced wine mixture, cover and simmer on low for 2.5 to 3 hours.

Add reserved mushrooms, sautéed onions, and garlic in the last 30 minutes of cooking.

Discard bay leaves and thyme stems. Adjust seasoning, let rest before serving, and garnish with parsley.