Preheat oven to 350 degrees F.
Into a high-speed blender, add cream cheese, cheddar cheese, garlic, and beer. Blend until well combined and smooth.
Add cornstarch and blend again to incorporate.
Pour cheese mixture into a prepared 5-inch ramekin dish. Bake, uncovered 25-30 minutes, until bubbly. Serve hot, warm, or room temperature.