Slow Cooked Potatoes with Mushroom and Ham

I needed a way to use up mushrooms and diced ham and I did happen to have a couple of pounds of potatoes sitting around too, which is kind of unusual for me.  A critical direction is turning up the heat to high when sauteeing the mushrooms.  This kind of caramelizes the mix and it smells so good.  Peeling the potatoes was the most difficult part of the whole thing, which tells you just how easy it was.  I did not use Gruyere cheese because I had a large offering of other cheese in my fridge and instead chose to use crumbled goat cheese.

• Ingredients
• 3 tablespoons (1/2 stick) unsalted butter
• 1 cup chopped yellow onion
• (about 1 medium onion)
• 1/2 pound button or shiitake mushrooms, or a mix of your favorite mushrooms, wiped clean, stemmed, and sliced
• 1 tablespoon chopped garlic (2 to 3 cloves)
• 1 ½ teaspoons salt
• 1 ½ teaspoons freshly ground black pepper
• 2 pounds Idaho potatoes, peeled and submerged in a bowl of water
• 4 ounces ham  (I used pre-diced)
• 4 ounces Gruyere cheese, grated 
• 1 cup low-sodium chicken broth
• 1 teaspoon thyme
• 1 cup milk

Directions

Melt the butter in a 12-inch skillet over medium heat. Add the onion and cook for 1 minute. Add the mushrooms, raise the heat to high, and continue cooking, stirring as needed, for 5 minutes. Add the garlic, ½ teaspoon of the salt and ½ teaspoon of the pepper. Remove from the heat and set aside. 

Generously coat a 6-quart slow cooker with cooking spray. Shingle the potatoes in two with ½ teaspoon of the salt and ½ teaspoon of the pepper. Top the potatoes with half of the mushrooms-onion mixture and gently spread it out in an even layer. Arrange half of the ham slices over the potatoes, top with half of the Gruyere, and pour in half of thechicken stock. Repeat with the remaining potatoes, salt, pepper, mushrooms mixture, and ham. Add the remaining ½ cup chicken stock. Using a metal spatula, gently press the ingredients so the layers are even. Tuck the thyme sprigs around the edges. 

Cook on high for 4 hours, or until the potatoes are tender. You can test for doneness by inserting the blade of a thin knife into the center. There should be little resistance. 

Drizzle in the heavy cream and cook for another 30 minutes. 

When the casserole is done, top it with the remaining Gruyere and the fresh thyme leaves. Turn off the cooker. Allow the potatoes to cool enough to set before serving, about 1 hour, covered.