Old-Fashioned Hamburger Stew

Heat oil in a large pot over medium heat. Add ground beef and onion; cook until beef is browned and onion is soft and translucent, about 5 minutes. Add potatoes, tomato purée, diced tomatoes, 12 cups water, Italian seasoning, beef bouillon, cooking sherry, garlic, Sriracha, Worcestershire sauce, black pepper, garlic powder, onion powder, red pepper flakes, rosemary, salt, and bay leaves to the pot. Bring to a boil.

Mix flour with remaining 1 1/2 cups of water in a small bowl until a thin slurry is formed. Slowly pour flour mixture into the boiling soup, stirring constantly, until well combined. Continue to boil soup, stirring often, until it begins to thicken, about 3 minutes.

Reduce the heat to a simmer and stir in frozen vegetables. Simmer, stirring occasionally, until potatoes and vegetables have cooked through, at least 20 minutes.