Let the Crispy Crowns sit on the counter to defrost for an hour or so until thawed.
In a large skillet cook the onion until tender and translucent. Add the beef and green pepper and cook over medium heat until no longer pink. Drain the mixture and place into a large bowl and set aside.
In a small bowl combine the soup, milk, rotel tomatoes, and sour cream. Whisk until smooth. Add to hamburger mixture and stir to combine. Add corn and 1 cup of cheddar cheese. Gently mix to combine.
Grease a 9x13 inch baking dish.
Layer half of the Tater tots on the bottom, pour the hamburger mixture over the top and then layer with the other half tater tots. Sprinkle with remaining 1/2 cup cheese
Bake at 375 for 25 - 30 minutes, or until golden brown and crunchy.