Cook the bacon: In a large pot or Dutch oven, cook the chopped bacon over medium heat until crispy, about 5-7 minutes. Remove the bacon and set it aside, leaving the rendered fat in the pot.

Brown the beef: Add the ground beef to the pot and cook until browned, about 5-7 minutes. Break it up with a spoon as it cooks. Drain excess fat if necessary.

Sauté the vegetables: Add the chopped onion, bell pepper, and minced garlic to the pot with the beef. Cook for 5 minutes, until the vegetables are softened.

Add the spices and tomato paste: Stir in the chili powder, cumin, smoked paprika, cayenne pepper (if using), and tomato paste. Cook for 2 minutes to let the flavors bloom.

Add the stout and broth: Pour in the low-carb stout and beef broth, scraping up any browned bits from the bottom of the pot. Bring the mixture to a simmer and let it cook for 20-25 minutes, stirring occasionally, until the chili thickens and the flavors meld.

Add bacon and adjust seasoning: Stir the crispy bacon back into the chili. Season with salt and pepper to taste.

Serve: Garnish with fresh parsley or green onions and serve hot. Pair with a dollop of sour cream or shredded cheese for an extra keto-friendly touch.