In a stockpot or large saucepan, brown ground beef with onion and garlic. Season with salt, black pepper and crushed pepper flakes. Drain.
Add beef stock, can tomatoes, potatoes, mixed veggies and Italian seasoning. Bring to a boil, cover, reduce heat and simmer at least until potatoes are tender, about 30 minutes. (This can definitely be simmered all day or even put together in a crockpot for the whole day.)
About 10 minutes before serving, stir in tomato paste. Let simmer uncovered and serve.
Notes
The stew will seem more like soup before adding the tomato paste. The tomato paste will thicken it up to a familiar stew consistency. But if you’d prefer a simple soup dinner instead, just omit the tomato paste.
Ground beef stew freezes perfectly so consider doubling or even tripling the recipe and get a few nights' worth of dinners at once.