Cook spaghetti:
Bring a large pot of salted water to a boil over high. Add spaghetti, and cook according to package directions. Drain spaghetti, and set aside.
Cook bacon:
While cooking spaghetti, cook bacon in a large Dutch oven over medium, stirring occasionally, until browned and crisp, about 11 minutes. Transfer bacon to a paper towel-lined plate using a slotted spoon; set aside. Do not wipe the Dutch oven clean.
Cook beef:
Increase the heat in the Dutch oven to medium-high. Add ground beef to the pan. Cook it, breaking the meat into smaller pieces with a wooden spoon. Stir occasionally until the beef is browned and no longer pink, about 6 minutes.
Add spices and herbs:
Add onion, garlic, pepper, and 1 teaspoon of salt to the Dutch oven; cook, stirring occasionally, until onion is translucent, about 4 minutes.
Add the chili powder, Worcestershire sauce, oregano, cumin, and garlic powder. Cook, stirring constantly, until fragrant, about 1 minute.
Stir the brown ale into the Dutch oven. Cook over medium-high heat, scraping up any browned bits from the bottom, until slightly reduced, about 2 minutes.
Stir in tomatoes, kidney beans, tomato sauce, hot sauce, and 1 teaspoon salt. Simmer over medium-high heat, then reduce the heat to medium. Cook, stirring occasionally, until it thickens slightly, about 5 minutes.
Combine spaghetti and meat sauce:
Remove Dutch oven from heat; stir in reserved spaghetti, and toss until spaghetti is fully coated in sauce. Serve topped with cheese, reserved bacon, and scallions.