In a bowl, mix provolone, ricotta, parmesan, and garlic. Season with salt and pepper.
Steam spinach for 1–2 minutes, then press to remove moisture.
Butter both sides of bread slices with 1 tsp butter per side.
On two slices, layer spinach and basil, then spread cheese mixture.
Sprinkle sun-dried tomatoes and press gently.
Top with remaining bread slices.
Heat skillet over medium-low, cover, and cook 4–6 minutes until golden.
Flip and cook uncovered for 2–3 minutes more.
Slice and serve warm.
