Preheat oven to 375°F (190°C) and lightly grease a 9x13 inch baking dish.
Cook ground beef in a large skillet over medium-high heat, breaking it apart as it browns.
Add onion and garlic halfway through cooking. Continue until beef is no longer pink and onions are translucent.
Remove excess fat from the skillet.
Stir in bell pepper and carrots. Cook for 3-4 minutes until softened.
Add frozen corn and cook for another 2 minutes.
Sprinkle with salt, pepper, and dried thyme.
Pour in Worcestershire sauce and stir to combine.
In a bowl, whisk together both cans of soup with milk until smooth.
Stir half of the soup mixture into the meat mixture.
Spread the meat mixture evenly in the prepared baking dish.
Pour the remaining soup mixture over the meat.
Sprinkle shredded cheddar cheese evenly over the casserole.
Arrange frozen tater tots in a single layer, covering the surface.
Bake uncovered for 45-50 minutes, until the tater tots are golden and crispy.
Let the casserole rest for 5-10 minutes before serving.
Sprinkle with fresh chopped parsley and serve warm.