Potatoes au Gratin with Caramelized Shallots and Smoked Gouda

This recipe is from a cooking class by Cindy Vescovi at Kitchen Affairs. It could also probably be called --Artery Clogging Spuds--but that name isn't nearly as appetizing. As far as I'm concerned, anything with potatoes and cheese is a "good thing."

5 pounds potatoes
9 shallots
3 cups heavy whipping cream
2 cups shredded smoked Gouda cheese
2 cups shredded Havarti cheese
olive oil
salt

• Using a mandolin slicer or food processor, slice the potatoes as thinly as possible. Chop the shallots. Saute the shallots in a little olive oil over medium heat for about 20 minutes, or until tender. Remove from the heat, strain off the oil, and set the shallots aside.
• Shred the cheese using a food processor or coarse grater.
• Preheat the oven to 375.
• Oil or butter a baking dish liberally. Place a single overlapping layer of potatoes into the pan. Sprinkle the slices with salt, one layer of each cheese, and some of the sauteed shallots. Pour a small amount of cream over the top. Repeat, layering the potatoes, salt, cheeses, shallots, and cream until the pan is full. Press on the sliced potatoes to remove any air. Fill the pan as completely as possible. Bake for 1 1/2 to 1 3/4 hours, until the potatoes are tender throughout. Cover with foil when the top starts to brown, after about 45 minutes. Can be baked ahead, covered with foil, and held for a couple of hours. Serve hot.