Prep the brisket: Preheat your oven to 150°C (300°F). Trim off any excess fat from the brisket, leaving a nice layer of about 1/2 inch. Drizzle the brisket with olive oil and season generously with salt and pepper.
Make the rub: Combine the smoked paprika, brown sugar, cayenne pepper, garlic powder, onion powder, smoked coriander, and chili powder in a small bowl. Rub the mixture all over the brisket, ensuring it covers every corner.
Sear the brisket (optional): This step adds an extra layer of flavor but isn't essential. Heat a large Dutch oven or oven-safe pot over medium-high heat. Sear the brisket on all sides until nicely browned.
Build the braising liquid: Add the chopped onion, carrots, celery, bay leaves, and thyme sprigs to the pot. Pour in the beer (or beef broth), beef broth, water, tomato paste, Worcestershire sauce, and molasses. Stir well to combine.
Slow-roast the brisket: Nest the brisket in the braising liquid, ensuring it's mostly submerged. Cover the pot tightly with a lid or foil. Transfer the pot to the preheated oven and roast for 4-5 hours, or until the brisket is fork-tender and falls apart easily.
Rest and shred: Carefully remove the brisket from the pot and let it rest for at least 30 minutes, tented with foil, before slicing or shredding. Strain the braising liquid into a saucepan and simmer until reduced slightly for a delicious pan sauce.
Serve and savor: Slice or shred the brisket and serve it with your favorite barbecue sides like baked beans, coleslaw, mac and cheese, and crusty bread. Drizzle the pan sauce over the brisket for extra flavor.