I don't know why this recipe isn't a 5-star recipe, it sure deserves to be! We loved this and this is the only hash brown casserole recipe I will make from now on (who needs cream of chicken soup?)! I did have to lighten up the recipe a bit - I used only 1/4 cup butter, half&half instead of heavy cream, and light sour cream. Instead of white onion, I used a bunch of green onions for color. The only asiago cheese I found at my store was a package of shredded asiago/parmesan blend. It was perfect! The ONLY think wrong with this recipe, as far as I can see, is that it says to season with salt and pepper after it's done baking. I would highly recommend seasoning the mixture before it goes in the oven. I stirred in 1/2 tsp. salt and 1/4 tsp. fresh ground black pepper. They were not bland or greasy at all!