Melt the butter in a pot over medium-high heat. Add the flour and cook it for a minute or so, stirring nearly constantly.
Whisk in the half-and-half, garlic powder, and cayenne pepper. Make sure that there's no lumps.
Stir in the corn. After about 10 minutes, it should start to bubble. Once it's bubbling, turn the heat down so it's simmering gently.
Cook the corn for another 15-20 minutes or until the sauce has reduced and the corn is nice and plump. Keep an eye on it, and stir it occasionally.
Add salt & pepper as needed (I'm pretty generous with the salt).
Notes
Here in Canada I buy a (750g/26.5 oz.) bag of frozen corn for this recipe (it equals 5 cups). If using less corn, add a bit less half-and-half (this recipe is pretty forgiving!).
Nutritional information is provided as a courtesy only and should be construed as an estimate rather than a guarantee. Ingredients can vary and Salt & Lavender makes no guarantees to the accuracy of this information.