1 large baking potato, peeled and cut into 1/2-inch dice
1 teaspoon ground cumin
1 bay leaf
4 ounces dried fideos noodles or spaghettini, crushed
Kosher salt and freshly ground pepper
In a soup pot, heat 2 tablespoons of the oil. Add the sirloin and cook over high heat until browned all over; transfer to a plate.
Heat the remaining 2 tablespoons of oil in the pot. Add the onion, bell pepper and garlic and cook over moderately high heat until softened, about 4 minutes. Add the stock, potato, cumin and bay leaf. Bring to a simmer and cook for 10 minutes.
Add the noodles and simmer until al dente, about 5 minutes. Return the meat and any accumulated juices to the pot and cook until warmed through, about 1 minute. Discard the bay leaf. Season the stew with salt and pepper, ladle into bowls and serve.