Ingredients:

  • 5 lbs Yukon Gold potatoes, sliced 1/8-inch thick
  • 1 medium yellow onion, shaved paper-thin
  • 3 cloves garlic, minced
  • 1 tsp Kosher salt
  • 1/2 tsp freshly cracked black pepper
  • 1.5 cups heavy cream
  • 1 cup whole milk
  • 3 tbsp all-purpose flour
  • 1 tsp fresh thyme leaves, chopped
  • 1/2 tsp ground nutmeg
  • 2 cups Sharp White Cheddar cheese, freshly shredded
  • 1 cup Gruyère cheese, shredded
  • 1/2 cup Parmigiano Reggiano cheese, finely grated

Instructions:

  1. Grease your slow cooker insert generously with butter or non stick spray.
  2. Use a mandoline to slice the 5 lbs Yukon Golds into 1/8 inch rounds. Aim for translucent edges to ensure even cooking.
  3. In a medium bowl, whisk together 1.5 cups heavy cream, 1 cup whole milk, 3 tbsp flour, minced garlic, thyme, nutmeg, salt, and pepper.
  4. Place one third of the potato slices in the bottom of the crockpot. Shatter the onion layers by sprinkling one third of the shaved yellow onion over the potatoes.
  5. Sprinkle one third of the Cheddar and Gruyère mix over the onion layer.
  6. Continue layering potatoes, onions, and cheese two more times. Keep the layers level to avoid cold spots in the middle.
  7. Slowly pour the cream mixture over the top.
  8. Cover and cook on High for 4 hours.
  9. 30 minutes before serving, sprinkle the 1/2 cup Parmigiano Reggiano on top. Cook until the edges are golden and crackling.
  10. Turn off the heat and let the pot sit uncovered for 15 minutes.