Deluxe Potatoes au Gratin

Every Christmas dinner in our family is hosted at my Aunt's home.  No matter what the menu, my Uncle makes his "Company Potatoes"; the recipe is a secret and I've not tried to reverse engineer them as they are awesome and his thing.  He is THE Potato Guy in our family.  He loves potatoes.  However, this Easter I was tasked with a potato side dish.  I knew the bar was set high, and I went for it.

Like many of my sauces, I needed to keep extra of each ingredient on hand to keep things flexible; just add more or less to the bechamel sauce based on your tastes and how the batch of sauce is behaving.  Of course, I am of the belief that you can never have too much garlic or too much pepper.  I wanted this to stand out and bring out different elements, so I used a bit of wine and added a touch of horseradish.

THE RECIPE--
1# thickly sliced pepper bacon
1 stick unsalted butter, divided, + more for lining baking dish
One large onion, halved then sliced thinly
6 cloves garlic
6 T flour
2 C whole milk
3/4 C half & half
Sea salt and freshly ground black pepper, to taste
3 - 4 dashes Tabasco sauce
3 - 4 dashes Worcestershire sauce
1 bunch fresh thyme leaves, minced
1 bunch fresh Italian flat-leaved parsley, minced
1/2 bunch fresh oregano leaves, minced
1/2 bottle dry white wine
2 t prepared horseradish, +/-, to taste - start off with a smaller amount then add more until you can just detect a hint of this flavor.
4-5 large russet potatoes peeled, 1/4" slices -- put in cold water until ready for cooking
1 C Romano or Parmesan cheese, grated
3 C shredded cheese blend, esp. sharp cheddar + more for garnish

Preheat oven to 400° F.

Broil pepper bacon until crisp.  Cool, chop finely and reserve.

In a large, deep skillet heat 2 T butter over medium flame.  Saute onions until pliable; add garlic and saute for another minute.  Season and set aside.

Return pan to medium flame; melt butter and whisk in flour, stirring constantly for 3 minutes.  Slowly add milk and half & half, stirring constantly.  Season and add herbs and wine.  Keep in mind these flavors will concentrate as the sauce reduces.  Add horseradish and taste.  Simmer lightly until reduced, stirring frequently.  Taste and adjust seasoning.  Gradually stir in the cheese and remove from the flame once it is melted.

Butter a large baking dish.  Place a layer of sliced potatoes in the bottom; season with salt and pepper, onion and garlic mixture, bacon and bechamel sauce.  Repeat this layering until the pan is full.  Top with more shredded cheese and cover with aluminum foil.  Bake at 400°F for approximately 1 1/2 hours.  Garnish with shredded cheese and fresh herbs.