Healthier Version of Joanna Gaines Scalloped Potatoes

Last week I ordered the Magnolia Table Cookbook by Joanna Gaines (this is her first cookbook, not the one that just came out.)  So far I have just made these scalloped potatoes and her chocolate coco-cola cake (which was amazing.)  But I have noticed most of her recipes are not what you would call low-fat. I mean, look at her.  She doesn't have to worry about it.

So today I made the Scalloped Potatoes, and did some major tweaks to the recipe.  One of the main reasons I made S.P. is because last Friday I bought turnips at the farmers market.  Now, I know I don't like turnips, and I am pretty sure my husband doesn't like turnips -- but the farmer's wife told me to substitute them for potatoes in scalloped potatoes. I wouldn't say this makes turnips delish, but it wasn't bad.  Next time I would just use potatoes.  I remembered seeing a scalloped potato recipe in the cookbook so here goes:

SCALLOPED POTATOS OR TURNIPS

(Joanna's ingredient is on the left, mine in CAPS)

6 Tablespoons unsalted butter -- I USED 3 TABLESOONS OF SALTED BUTTER
6 russet potatoes (about 3 lbs) scrubbed, peeled, and cut into 1/4" slices
     -- I DID THE SAME THING WITH THE TURNIPS
6 garlic cloves, minced -- I USED ABOUT 3 TEASPOONS OF THE MINCED TYPE IN THE JAR
1/2 ONION CHOPPED (she did not have this)
2 Tablespoons flour -- I UPPED IT TO 3 TABLESPOONS
2 cups heavy cream -- I USED 1 CUP HALF AND HALF
1 cup whole milk -- I USED 1 CUP SKIM MILK
1 CUP PLAIN YOGURT (she did not have this)
FRESH PARSLEY (she did not have this)
8 ounces Gruyere cheese, grated -- I USED 4 OUNCES GRATED ITALIAN BLEND
     (8 oz was too much)
1/2 tsp black pepper (I USED 1 TSP MRS DASH TO BOOST THE FLAVOR)
salt to taste
2 Tablespoons minced chives -- I do have these in my herb garden so I actually used them --

 with no substitutions!

1.Preheat oven to 350 degrees.  Butter 9x13" baking dish.
2. Bring a large pot of generously salted water to rolling boil.  Add potatoes and simmer until tender but not falling apart -- about 8 minutes.  Longer for turnips.  Drain thoroughly and set aside.
3. In same pot throw in the chopped onion with a little olive oil, saute until tender.  Add the garlic and butter.  Increase heat to medium and whisk in the flour.  Cook, stirring constantly for 2-3 minutes until lightly browned and fragrant.
4. Whisking constantly, slowly add the half and half, milk and yogurt.  Continue whisking until the sauce is smooth.  Add the parsley, cheese, Mrs. Dash and salt.  Wisk gently, until the cheese is melted.
5.  Arrange the potatoes (or turnips) in the prepared baking dish and pour the sauce over them.  Bake until warmed all the way through and lightly browned on top -- 25-45 minutes.  Top with chives and serve.