Preheat oven to 350 degrees F. Place sliced peppers in baking dish and drizzle 1 tablespoon of olive oil, and a sprinkle of sea salt and black pepper.
Bake for about 30 minutes or until the peppers start to get dark. Remove from oven and allow to cool.
In a sauté pan add 1 tablespoon of olive oil, chopped garlic and spinach. Sauté until spinach is wilted.
Start building your sandwiches by placing four slices of sourdough bread on the counter.
Cover each slice of bread with a total of 4 cheese slices on each slice of bread. ( 2 to cover the bread, and two deep).