In a medium, coverable pot, melt butter on medium high heat. Add the flour and stir to form a roux (the texture of the flour should look like a soft paste). Stir and let heat for about 30 seconds. Add Marsala wine, chicken broth and the My Leaning Tower Italian Blend or alternate spices, salt and stir. Bring to a low rolling boil, and then take off heat to let thicken. Salt to taste and then cover and set aside

Preheat oven to 350 degrees

Grease a 9 X 12 casserole dish. Then slice the potatoes into thin discs. Use a mandolin if available to ensure uniform slices of potatoes. Place a layer of potatoes on the bottom of casserole pan followed by some onions.

Then pour half of the sauce over it, followed by a sprinkling of the Parmesan cheese. Then top with another layer of potatoes, onions and sprinkling of cheese, and another until all ingredients (except for the cheese) are used.

Top with rest of the sauce and cheese. Cover with tin foil and bake for about 35 minutes. Then remove tin foil cover and bake for an additional 20 minutes.

Carefully drain any excess oils from the cheese if there are any by gently tilting the pan until the oils drain.

Broil for 5 minutes by checking after 3 minutes and then each minute until you get a golden brown top and some of the potatoes crisp.

Let sit for about 5-10 minutes and then serve.