Preheat your oven to 275°F (135°C) and lightly grease a 9×13-inch (23×33 cm) baking dish.
Add the beef stew meat, potatoes, carrots, onions, and peas into the prepared dish. Season everything with salt and pepper, then stir well.
Pour both the tomato soup and cream of mushroom soup over the top of the mixture, then stir gently until everything is combined.
Tightly cover the baking dish with foil, then bake for 5 hours.
After baking, let the dish rest for 5-10 minutes before serving.