Ingredients:
- 8 slices sourdough bread
- 1 lb Gruyere cheese, thinly sliced
- 1 large sweet onion, thinly sliced
- 1 cup apple cider vinegar
- 1/4 cup granulated sugar
- 1/2 tsp salt
- 1/4 tsp black pepper
- 2 tbsp butter, softened
Instructions:
Apple cider vinegar, sugar, salt, and black pepper should all be mixed together in a small saucepan
Bring it to a boil, then add the sweet onions that have been cut short
Turn down the heat and let the onions simmer for 10 minutes, until they are soft and almost clear
Take it off the heat and let it cool down
Remove any extra liquid
Set a grill pan or pan for making sandwiches on medium heat
Place some soft butter on one side of every sourdough slice
Put Gruyere cheese on the side of 4 slices of bread that hasnt been buttered
Add the pickled sweet onions on top, and then cover with the rest of the bread slices, buttered side out
Put the sandwiches on the grill pan or panini press that has been heated up
Toast the bread and melt the cheese for three to four minutes on each side
Take it off the heat, cut it in half, and serve it hot









