Preheat your oven to 400°F (200°C).

Heat a large skillet over medium. Add the ground beef and brown it, breaking it up with a spoon. Drain any excess fat.

Add the diced onion and carrots to the skillet. Cook until the onion is translucent and the carrots begin to soften, about 5–7 minutes.

Stir in the peas, beef broth, tomato paste, and Worcestershire sauce. Season with salt and pepper. Bring to a simmer and cook for about 10 minutes, until the mixture thickens slightly. Taste and adjust seasoning.

Transfer the beef mixture to a baking dish and spread it into an even layer.

Spoon the mashed potatoes over the meat. Smooth with a spatula or fork for a rustic finish. If you like, sprinkle the top with shredded cheddar cheese.

Bake for 25–30 minutes, until the top is golden and the filling is bubbling at the edges.

Remove from the oven and let rest for 5–10 minutes before serving.