Heat the oil in a large skillet over medium heat. Sauté the garlic clove until golden brown, 2-3 minutes. Remove and discard the garlic. Add the spinach, capers and crushed red pepper to the skillet.
In the meantime, cook the ravioli according to package instructions and drain, reserving ½ cup of cooking water. Add the ravioli to the skillet and toss gently to incorporate, adding the pasta cooking water a little at a time to achieve a sauce-like consistency.
Add the cheese and season with salt and pepper to taste. Divide among plates and sprinkle with more cheese and chili flakes, if desired.