Cook the bacon bits in a large Dutch oven over medium heat, stirring often, until browned, for about 8 minutes. Remove all but 1 tablespoon of bacon grease, leaving the bacon in the Dutch oven.
Add the onion, bell pepper, chili powder, cumin, coriander, oregano, crushed pepper flakes, and cayenne and cook, stirring occasionally, until they soften, about 10 minutes.
Increase the heat to medium-high and add half the ground beef. Cook, breaking up the beef with a spoon, until no longer pink and starting to brown, about 3-4 minutes.
Add the remaining ground beef and minced garlic, breaking up the beef with a spoon until no longer pink and beginning to brown, about 3-4 minutes.
Add the diced tomatoes, tomato puree, black beans, and season with sea salt and freshly cracked pepper to taste; stir until well combined. Bring to a boil, then reduce heat to low and simmer, covered with a lid, stirring occasionally, for 1 hour.
Remove the cover and simmer for 1 hour longer, stirring occasionally, until the beef is tender and the chili is dark, rich, and slightly thickened. Taste and season with sea salt and freshly cracked pepper, if needed.
Side Note: If the chili begins to stick to the bottom of the pot during the second hour of cooking, stir in 1/2 cup of water and continue to simmer.