French Onion Soup Open-Faced Sandwich
by
Clinton Kelly
Clinton takes all the cozy, comforting flavors of classic French Onion Soup and flips them into the ultimate open-faced sandwich. Buttery onions, melty Gruyère, and creamy Boursin on crisp sourdough — it’s everything you love about the soup, without the spoon.
Prep Time:
15 minutes
Cook Time
30–40 minutes (including caramelizing and baking)
Serves:
4 Servings
Level:
Beginner
4 slices sourdough (or other good-quality bread)
2 tbsp butter
3 medium yellow onions, thinly sliced
¼ tsp kosher salt
1 tsp dried thyme
1 cup beef broth
Splash of red wine (optional)
5.3 oz Boursin cheese (any flavor)
4 oz Gruyère cheese, shredded
Optional: ½ tsp sugar (if onions aren’t browning)
Ingredients
Step 1 In a large skillet, melt butter over medium heat.
Step 2 Add onions, salt, and thyme. Cook 25–30 minutes, stirring every few minutes until deeply caramelized. (If not browning after 20 minutes, stir in sugar.)
Step 3 Deglaze the pan with beef broth and red wine; bring to a boil and reduce until most liquid evaporates. Onions should be thick and jammy.
Step 4 (Optional prep step) Make ahead: Cool and refrigerate onions up to 2 days; reheat before using.
Step 5 Preheat oven to 400°F.
Step 6 Lightly toast the sourdough slices, then spread each with a thin layer of Boursin cheese.
Step 7 Spoon caramelized onions evenly on top, then sprinkle with shredded Gruyère.
Step 8 Bake 8–10 minutes, until the cheese is fully melted and bubbly.
Step 9 Serve warm with a crisp green salad.
Instructions
• Serve with: lightly dressed green salad