Description

A decadent French Onion and Apple Grilled Cheese sandwich, combining caramelized onions infused with apple cider, fresh herbs, crisp prosciutto, sweet honeycrisp apple slices, and a melty blend of fontina and gouda cheeses between crispy, olive oil-brushed sourdough bread slices. This savory and slightly sweet grilled cheese brings gourmet flavors to a classic comfort food.

Ingredients

Scale

Caramelized Onions

3 tablespoons salted butter
2 yellow onions, thinly sliced
Kosher salt and black pepper, to taste
3/4 cup apple cider, divided
1 tablespoon fresh thyme leaves
1 tablespoon chopped fresh sage
1 pinch crushed red pepper flakes

Sandwich Components

4 slices prosciutto (optional)
8 slices sourdough bread
2 tablespoons extra virgin olive oil
1 1/2 cups shredded fontina cheese
1 1/2 cups shredded gouda or white cheddar cheese
1 honeycrisp apple, thinly sliced
Additional 1/2 tablespoon butter and 2 sage leaves for finishing

Instructions

Caramelize the Onions: Melt 2 tablespoons of the salted butter in a large skillet over medium-high heat. When the butter shimmers, add the thinly sliced onions and cook for 3 minutes until softened. Pour in half of the apple cider, season with kosher salt and black pepper, and cook for another 5 minutes until the cider mostly evaporates. Add the remaining cider and continue cooking for 5 more minutes until the onions turn golden and caramelized. Stir in the fresh thyme, chopped sage, and crushed red pepper flakes, cooking for an additional minute before removing from heat.
Cook the Prosciutto: In another large skillet over medium heat, cook the prosciutto slices until they become crisp, about 2 minutes per side. Remove and set aside.
Prepare the Bread: Brush the outside of each sourdough slice evenly with extra virgin olive oil. On the non-oiled side of half the slices, layer the shredded fontina cheese and shredded gouda or white cheddar cheese evenly. Top the cheeses with the caramelized onions, thin apple slices, and prosciutto (if using). Cover with the remaining bread slices, olive oil side facing out.
Grill the Sandwiches: Heat the skillet over medium heat and place 1-2 sandwiches in the pan at a time. Cook each sandwich until golden brown on each side, about 3-5 minutes per side. During the last minute of cooking, add 1/2 tablespoon butter and 2 fresh sage leaves to the skillet to infuse flavor and crisp the sage leaves. Remove the sandwiches once both sides are toasted and cheese is melted.
Serve: Serve the grilled cheese sandwiches immediately, topped with the crispy sage leaves for added aroma and texture. Enjoy this comforting, flavorful meal fresh off the stove.

Notes

Prosciutto is optional; omit for a vegetarian version.
Use freshly shredded cheese for best melting and flavor.
Adjust seasoning to taste, especially salt, since prosciutto and cheese add saltiness.
For easier slicing, let the sandwiches rest for a minute before cutting.
Use a sturdy skillet or griddle to ensure even toasting.

Prep Time: 15 minutes
Cook Time: 20 minutes
Category: Sandwich
Method: Frying
Cuisine: French-American

Keywords: French onion grilled cheese, apple grilled cheese, caramelized onion sandwich, prosciutto grilled cheese, sourdough sandwich, fontina and gouda sandwich