Begin by preparing your ingredients. Slice onions and mince garlic. Pat the roast dry and season with salt and pepper.

In a Dutch oven, heat olive oil and sear the roast until browned on all sides, about 10 to 12 minutes.

Add sliced onions and cook over medium heat until translucent, then lower heat and caramelize for about 20 minutes. Add minced garlic in the last 8 minutes.

Sprinkle flour over onions, then deglaze with red wine and beef broth. Return the roast, add thyme and bay leaves, and bring to a simmer.

Cover and transfer to a preheated oven at 300°F. Cook for 3 to 4 hours until tender.

Remove from oven and let cool slightly. For best flavor, refrigerate overnight before serving.