In a medium bowl, combine the ricotta cheese with a pinch of salt, black pepper, and optional seasonings like garlic powder or red pepper flakes for extra flavor. Stir until creamy and well mixed.

Take two slices of bread and spread a generous layer of the ricotta mixture on one side of each slice. Layer sun-dried tomatoes and fresh spinach on top, followed by mozzarella or provolone cheese, and close with the other slice of bread, ricotta side down.

Warm a non-stick skillet over medium heat, add butter or olive oil, and let it melt.

Carefully place the sandwiches in the skillet, pressing gently with a spatula. Cook for about 3-5 minutes until the bottom is golden brown.

Flip the sandwiches and cook for another 3-5 minutes on the other side until golden brown and the cheese is melted.

Remove from the skillet, allow to cool for a moment, then slice in half and serve hot.