Melt butter in a medium saucepan over medium heat. Stir in flour until smooth, and cook for 1 minute, stirring constantly. Slowly pour in milk, and stir until thickened. Season with salt, pepper, thyme, and garlic powder.
Stir in corn, and transfer mixture to a 9x13 inch baking dish. Sprinkle cheese over the top.
Bake for 25 minutes in the preheated oven, or until cheese is melted and bubbly.
Interesting Facts
This dish is a classic American side dish, often served alongside grilled meat or at holiday meals.
The dish can also be served as a main course if served with bread or a salad.
You can also add other ingredients, such as cooked bacon, diced jalapeno peppers, or diced bell peppers to the dish.