1. Heat oil in a large nonstick skillet over medium-high. Saute the onion and garlic until golden (2 minutes).
2. In a separate bowl, whisk together milk, flour, mustard, thyme, and pepper in a small bowl and mix well.
3. Slowly stir the milk mixture into the onions in the skillet then add the corn. Mix well until the mixture comes to a boil and thickens (3 minutes). Stir constantly.
4. Serve hot, topped with cheddar cheese.