Preheat oven to 350 degrees. Brown ground meat then cook onion and garlic in with the meat just until they are softened. Put in a dutch oven (this works better than a regular casserole dish).
Pour tomatoes and corn (with juices) on top of meat. Then spread yogurt over the top of meat and vegetables. Spread cheese over the top of yogurt. Season with salt and pepper to your tastes. Then top casserole with tater tots (cover the whole top).
Cook uncovered for 45 minutes to 1 hour until tater tots are crispy and everything is heated thru. Let sit for 10 minutes then serve.