Sauteed Chard, Apple, and White Cheddar Grilled Cheese

I really love a great grilled cheese sandwich and I love this one so much that I ate it for lunch and dinner on the same day.  I don't have much to say other than that there is just something about toasted bread sandwiching oozy melted cheese that shouts comfort foods from the roof tops and this one may be one of my very favorites!

Sautéed Chard, Apple, and White Cheddar Grilled Cheese

1 tablespoon olive oil, divided
4 leaves of Swiss chard, stems removed and thinly sliced
1/3 cup fresh grated white cheddar
1/4 cup fresh grated mozzarella
1 heaping tablespoon finely minced red onion
4, 1/2" slices whole grain bread
1/2 apple (honey crisp, pink lady, braeburn), thinly sliced
1 1/2 tablespoons whole grain mustard
1 tablespoon good quality mayonnaise
1 tablespoon butter, softened
Kosher salt

Heat 1 teaspoon olive oil in sauté pan.  Once hot, add thinly sliced chard to pan along with a pinch of kosher salt.  Keep the chard moving to release pockets of steam to help let the moisture out so that the chard doesn't become soggy in the sandwich.  Cook chard until just wilted and tender.  Remove chard from pan and set aside.

While preparing the sandwiches, preheat your cast iron or grill pan over medium heat with the remaining 2 teaspoons of oil.

Combine both cheeses and the finely minced red onion.

On one side of each slice of bread, spread a layer of both the mustard and mayonnaise and spread to edge of each slice.  Layer three to four slice of apple on top of two pieces of bread.  Divide the shredded cheese on top of the apple slices in an even layer.  Divide the sautéed chard on top of the cheese and top with remaining slices of bread.  Lastly, spread a thin layer of butter on the outside of both sides of each sandwich and lightly sprinkle with kosher salt.

Add sandwiches to cast iron or grill pan and cook until golden on both sides and cheese is melted through.

Recipe adapted from Sprouted Kitchen