Cook the Bacon/Pancetta: In a large Dutch oven over medium heat, cook the bacon and/or pancetta until crispy. Remove and set aside, leaving all the drippings in the pot.
Season & Sear the Beef: In a bowl, toss 2.5 pounds chuck roast, trimmed and cut into cubes with 2 tablespoons Kinder's Buttery Steakhouse seasoning, 1 tbsp of 2 tablespoons Creole Trinity & Herb seasoning (divided), and 2 tablespoons flour until evenly coated. Add beef to the pot in batches and sear on all sides until a deep crust forms. Remove and set aside.
Build the Flavor Base: Add 1 onion, diced, 5 carrots, cut into large chunks, 4 celery stalks, cut into large chunks, and 2 tablespoons minced garlic to the same pot. Let them sweat and soften for a few minutes. Splash in about 1 tbsp of Guinness and scrape up all the browned bits from the bottom — that's flavor. After 2–5 minutes, add 1 tablespoons tomato paste (heaping) and let it cook slightly against the bottom of the pot, then stir it into the vegetables. Add the remaining 1 tbsp of 2 tablespoons Creole Trinity & Herb seasoning (divided).
Add the Guinness: Pour in the remaining Guinness. Let it simmer for 4–5 minutes to cook off the alcohol and deepen the flavor.
Add Remaining Ingredients & Braise: Preheat oven to 325°F. Add 16 ounces beef broth or stock, 2 cups water mixed with 1 tablespoons roasted beef bouillon base, 2 tablespoons Worcestershire sauce, extra Kinder's seasoning to taste, salt and pepper, 3 sprigs fresh thyme, the reserved bacon/pancetta, and the seared beef. Stir to combine, cover, and place in the oven for 60 minutes
Add Potatoes & Finish Braising: After 90 minutes, add 0.5 pounds small golden potatoes, quartered to the pot. Return to the oven and cook for another 1–2 hours, until the beef is fork-tender and the broth is rich and thick. Taste and adjust seasoning as needed. For extra depth, add another half bottle of Guinness during the second hour.
Thicken (Optional): If you'd like a thicker stew, ladle out a small amount of broth into a bowl, whisk in 1 tablespoons cornstarch (optional, for thickening), then stir it back into the stew. Simmer on the stovetop for a few minutes until thickened.