Yukon Gold and Sweet Potato Gratin

I had a whole host of stuff leftover from our two Thanksgiving celebrations that I was trying to use up tonight. I found a recipe for a two potato gratin on Epicurious and adapted it to use up the myriad bits of fresh herbs, 1/2 carton of cream, etc.

This was sooooo good. However. It is not even remotely good for you. In fact, I am pretty sure I could hear my ass growing and my arteries clogging with every bite. I have posted the recipe as I made it, and afterwards my thoughts on how I will adapt it for a healthier version that we can eat more often.

Yukon Gold and Sweet Potato Gratin
6 baby Yukon Gold potatoes, peeled
1 sweet potato, peeled
1 c. heavy cream
2 tbsp. butter (although even if you are making the unhealthy version, I think you can leave this out all together - it made gross little oily puddles)
1 clove garlic, minced
1/2 c. sharp cheddar, shredded
1/2 c. monterey jack, shredded
1/2 tbsp. fresh rosemary, chopped
1/2 tbsp. fresh thyme, chopped
1 tbsp. fresh Italian parsley, chopped
Salt and pepper

Preheat oven to 400.

Slice potatoes to 1/8 inch thickness using a food processor or mandoline.

Bring cream, butter (if using) and garlic to a simmer over medium heat. Remove from heat.

Spray a 8x8 inch baking dish with cooking spray.

Spread half of the potatoes in the bottom of the dish. Season with salt and pepper. Sprinkle with half of the herbs. Top with half of the cheese.

Repeat for a second layer.

Pour the cream mixture over the top. Cover tightly with foil.

Bake at 400 for 25 minutes. Remove foil. Bake for an additional 25-30 minutes or until potatoes are cooked through.

Now, my thoughts for a healthier version:
The heavy cream is what really makes this dish bad news. I would not recommend replacing the cream with lowfat milk because the dish will end up watery. Rather, I would make a simple bechamel sauce with lowfat milk (recipe to follow) and use that instead of the cream and butter. Bechamel is thickened with flour, so it still has that creamier texture.

You can also reduce the amount of cheese (though what fun is that) or use reduced fat cheese. I don't like using reduced fat cheeses in hot dishes because it just doesn't melt right. For this recipe, I would probably opt to use a stronger flavored cheese like Swiss or Gruyere and cut back on the cheese by about 1/4 cup.

Finally, you could opt to use all sweet potatoes or use a higher proportion of sweet potatoes to Yukon Golds.

Bechamel sauce:
2 tbsp. butter
2 tbsp. flour
1 1/4 c. milk, heated

Melt the butter over medium heat in a saucepan. Slowly whisk in the flour and cook for about two minutes. Slowly pour in the heated milk and whisk. Bring to a boil, reduce the heat and let it cook for another 2-3 minutes.

For the potato gratin, stir in the minced garlic after the milk and use in place of the cream and butter.