Roast Beef with Caramelized Onions on Gorgonzola Toast from Closet Cooking

Tender roast beef served with sweet caramelized onions over ciabatta buns topped with a gorgonzola sauce that is broiled until the sauce is bubbling and golden brown. What a perfect way to enjoy some leftover roast beef!

Servings: makes 4 servings

Prep Time: 10 minutes
Cook Time: 50 minutes
Total Time: 1 hour
  • 1 tablespoon olive oil
  • 4 cups onion, sliced
  • 1/2 cup water
  • 1 teaspoon sage, thinly sliced
  • 2 tablespoons butter
  • 2 tablespoons flour
  • 1 cup milk
  • 2 ounces gorgonzola (or other blue cheese or gruyere), crumbled
  • salt and pepper to taste
  • 1 tablespoon sage, thinly sliced
  • 4 ciabatta buns, cut in half and lightly toasted
  • 1 tablespoon sage, thinly sliced
  • 1 pound roast beef, warm and thinly sliced
  1. Heat the oil in a pan over medium heat.
  2. Add the onions and water and cook, covered, until completely tender and caramelized and golden, about 40-50 minutes, adding more water as needed.
  3. About 30 minutes in, melt the butter in a pan over medium heat and cook until it starts to brown, about 2-3 minutes.
  4. Sprinkle in the flour and cook stirring until it starts to brown, about 2-3 minutes.
  5. Whisk in the milk and simmer until the sauce thickens, about 3-5 minutes.
  6. Mix in the cheese and sage and cook until the cheese has melted and remove from heat, about 2-3 minutes.
  7. Spread the sauce over the bottom of the buns and broil until bubbling and golden brown, about 1-2 minutes.
  8. Top the cheese buns with the roast beef and caramelized onions.