Ingredients:

  • 2 lbs Yukon Gold potatoes, peeled and sliced into 1/8-inch rounds
  • 1.5 lbs lean ground beef (90/10)
  • 1 tbsp extra virgin olive oil
  • 1 large yellow onion, finely diced
  • 3 cloves garlic, minced
  • 1 tsp dried thyme
  • 1 tsp smoked paprika
  • 1.5 tsp sea salt
  • 1 tsp cracked black pepper
  • 3 tbsp unsalted butter
  • 3 tbsp all-purpose flour
  • 2.5 cups whole milk, room temperature
  • 3 cups sharp cheddar cheese, freshly shredded
  • 1/2 tsp Dijon mustard

Instructions:

  1. Peel the 2 lbs Yukon Gold potatoes and slice them into 1/8 inch rounds. Note: Keep them in a bowl of cold water if you aren't using them immediately to prevent browning.
  2. Heat 1 tbsp olive oil in a large skillet and add the diced onion. Cook 5 minutes until translucent and soft.
  3. Add the 1.5 lbs ground beef to the skillet. Cook 8 minutes until browned and no pink remains, breaking it up with a wooden spoon.
  4. Stir in the minced garlic, 1 tsp thyme, 1 tsp smoked paprika, 1 tsp salt, and 1 tsp pepper. Sauté 1 minute until fragrant.
  5. Tilt the pan and spoon out any excess liquid. Note: This prevents the casserole from becoming greasy during the bake.
  6. In a separate saucepan, melt 3 tbsp butter over medium heat, then whisk in 3 tbsp flour. Cook 2 minutes until it smells slightly toasted.
  7. Slowly whisk in the 2.5 cups room temperature milk. Simmer 5 minutes until thickened, then whisk in the Dijon mustard and 2 cups of the cheddar cheese until melted.
  8. Grease your baking dish, lay down half the potatoes, then all of the beef mixture, followed by the remaining potatoes.
  9. Pour the velvety sauce evenly over the layers, making sure it seeps down into the crevices.
  10. Cover with foil and bake at 375°F (190°C) for 30 minutes. Remove foil, sprinkle the remaining 1 cup of cheese, and bake 15 minutes until golden and bubbling.