Set up the smoker. Preheat it to 375 degrees F to cook the scalloped potatoes. Use oak wood for smoke flavor.
Slice potatoes using a mandolin slicer. You will get sliced potatoes of the same thickness and size.
Take a large frying pan and place it on medium heat, add butter to it and melt it. Once the butter is melted add the onion to the melted butter and sautee it until it becomes tender and semi-transparent.
Add minced garlic cloves to this frying pan and saute them for about 2-3 minutes more.
Now add flour into the frying pan and mix it well. Stir it until it is well combined. Then add the remaining ingredients, which are chicken stock, milk, salt, pepper, and thyme.
Stir the sauce thoroughly until everything is combined. When the sauce begins to simmer, remove it from the heat.
Take a baking dish and brush it with some oil. Now Place the thinly sliced potatoes in the dish and add a layer of this creamy sauce that you prepared and add shredded cheese over it. Make 2 layers of these things.
Place the baking dish in the smoker and close the lid. Cook it for about 1 and a half hours or until the potatoes are cooked.
Once cooked remove the baking dish from the smoker and serve this amazing dish.