Preheat the oven to 375°F.
In a dutch oven or skillet, heat the olive oil and cook the ground beef breaking it apart with a wooden spoon until it’s no longer pink. Drain fat if needed. Season with salt and pepper.
Add the onion, and cook for 2-3 minutes or until it’s translucent, add the garlic and cook for 30 seconds.
Add tomatoes, corn, sour cream, and 1 cup of cheddar. Cook until the cheese has melted and everything is well incorporated. Remove from heat.
Pour the creamy mixture into the casserole dish, top with the remaining cheese, and then arrange the tater tots on top.
Bake for 30-35 minutes.
Garnish with fresh parsley and serve.