Preheat the oven to 400°F.
Add the sweet corn, whipping cream, and milk to a medium heavy-bottomed pot. Bring the mixture to a boil, then simmer for 5 minutes.
Heat the butter and garlic in a separate pan. Cook for 1 minute, until the butter melts and the garlic is fragrant. Sprinkle the flour over the butter and stir until a smooth, thick roux forms.
Add the roux to the simmering corn mixture. Cook for another 3-5 minutes, until the mixture is thick and creamy.
Add the sugar, Italian seasoning, black pepper, and salt to the corn mixture. Stir until well combined.
Transfer the corn mixture to a casserole dish. Sprinkle the Parmesan cheese and crushed red chili flakes evenly over the top.
Bake the casserole for 10 minutes. Then broil for 3-5 minutes, until the cheese is melted and lightly browned in spots.
Sprinkle the casserole with freshly chopped parsley and serve immediately.