Sweet Potato &
Brussel Sprout Gratin
Yield: 10-12 SErvings | Prep Time: 1 Hour | Cook Time: 40 Minutes


  • 2 strips thick cut, smoked bacon, chopped
  • 2 Tbsp. butter
  • ¼ C. finely chopped shallots
  • 2 cloves garlic, minced
  • 6 Tbsp. all-purpose flour, divided
  • 1 tsp. chopped fresh thyme
  • 2 C. whole milk
  • 8 oz. grated Parmigiano-Reggiano cheese
  • ½ tsp. salt


  • ½ tsp. pepper
  • 1/8 tsp. cayenne pepper
  • 1 lb. russet potatoes, peeled and sliced very thin (1/8”)
  • 1 lb. sweet potatoes, peeled and sliced very thin (1/8”)
  • 12 oz. Brussels sprouts, shaved
  • 8 oz. Gruyere cheese, shredded


  1. Preheat oven to 375°F.
  2. In a medium saucepan, cook the bacon over medium-high heat until lightly crisped.
  3. Add the butter and heat until melted.
  4. Add shallots and garlic and cook 2 minutes, stirring constantly.
  5. Add ¼ cup of the flour to the pot and stir constantly for 2 minutes.
  6. Add the thyme, then slowly add the milk, stirring constantly.
  7. Turn heat down to medium and cook, stirring, until slightly thickened (3 min.).
  8. Stir in the Parmigiano-Reggiano and cook until the cheese is melted.
  9. Add salt, pepper and cayenne then remove from heat.
  10. Cook the russets and sweet potatoes in boiling water for about 4 minutes or until almost tender.
  11. Drain the potatoes then spread them out on a couple of large baking sheets and allow them to release steam for about 5-10 minutes.
  12. Spray a 9x13 pan with cooking spray.
  13. Line the bottom of the pan with half the russets and sweet potatoes then half of the Brussels sprouts.
  14. Spread half of the cheese sauce over the top of the Brussels sprouts.
  15. Repeat the layering and then top with the remaining cheese sauce.
  16. Top with Gruyere and bake for 35-40 minutes.
  17. Let stand 10 minutes before serving.