Preheat oven to 400 degrees F (200 degrees C).
Use a mandolin slicer to thinly slice organic potatoes
Spray a 2 qt or larger casserole dish with non-stick cooking spray.
Layer 1/2 of the potatoes into bottom of the prepared casserole dish. Set aside
In a medium-size saucepan, melt 2 Tbs Horizon Organic butter over medium heat.
Mix in the organic flour and stir constantly with a whisk for one minute.
Slowly add Horizon Organic Whole Milk while whisking.
Cook until mixture has thickened and is smooth and creamy.
Add salt, and pepper, stir well.
Stir in 6 ounces Horizon Organic Shredded Cheddar Cheese and continue stirring until melted, and totally smooth, about 30 to 60 seconds. Remove from heat.
Pour half the Horizon Organic Shredded Cheese sauce over the sliced potatoes.
Sprinkle 1 cup Horizon Organic Shredded Mexican Blend Cheese over the top
Add remaining potatoes and then top with the remaining cheese mixture.
Add a thin layer of Horizon Organic Shredded Cheese on top, and cover the dish with aluminum foil.
Bake 1 1/2 hours in the preheated oven.
Remove aluminum foil and bake another 10 minutes until cheese is melty and a little crisp on the edges.
Garnish with organic chives