Sweet Potato Croque Monsieur
This vegetarian riff on a traditional croque monsieur takes all the classic elements (think: melty Gruyère cheese, golden bread, and creamy béchamel) and swaps in roasted sweet potatoes for ham, giving it a sweet-salty kick of umami that’s perfect for any meal.
Ingredients
For the Potatoes:
- 2 medium sweet potatoes, peeled and sliced into ¼-inch-thick rounds
- 2 tbsp. olive oil
- 3 tbsp. maple syrup
- 1 tbsp. sesame oil
For the Béchamel:
- 1 tbsp. unsalted butter
- 1 tbsp. all-purpose flour
- 1 cup whole milk
- ⅛ tsp. nutmeg
- Salt and pepper, to taste
For the Sandwiches:
- 4 hamburger buns
- 1-½ cups Gruyère cheese, grated
- 2 tsp. Dijon mustard
Instructions
- Pre-heat the oven to 425°F.
- Line a baking sheet with parchment paper.
To prepare the potatoes:
- Using a medium bowl, toss the sweet potato slices with the olive oil, maple syrup, and sesame oil.
- Spread in an even layer on the baking sheet.
- Place in the pre-heated oven and bake for 20 to 25 minutes, until fork tender but not overly soft.
- Once they’re cooked, remove from the oven; set aside to cool, but don’t turn off the oven.
To prepare the Béchamel:
- While the sweet potatoes are roasting, melt the butter in a medium saucepan, over medium-low heat; add the flour and whisk constantly for about 1 minute until a paste forms.
- Slowly drizzle in the milk, whisking constantly; continue to cook and stir until the sauce thickens, about 5 to 10 minutes and the whisk starts to leave tracks in the sauce.
- Remove from the heat and stir in the nutmeg, salt and pepper.
To assemble the sandwiches:
- Split and lightly toast the burger buns in the oven or a toaster until lightly browned; place them on a baking sheet.
- Spread a thin layer of Dijon mustard over the bottom half of the buns and top with a thin layer of the béchamel.
- Cover the béchamel with half of the grated cheese; top with the sweet potato slices.
- Place the top bun on each sandwich; cover the tops of the buns with the rest of the sauce and the remaining cheese.
To bake the sweet potato croque monsieurs:
- Place the baking sheet in the oven and bake for 10 to 15 minutes or until the cheese is melty.
- Switch the oven to broil and bake for an additional 1 to 2 minutes until the cheese is lightly browned and a little crispy for that signature croque monsieur look.