Bring a large pot of salted water to a boil and cook the pasta al dente. Reserve ½ cup of the pasta cooking water and drain the pasta. Return the drained pasta to the hot pot.
While the pasta is cooking, prepare the cheese mixture and sauce. In a small mixing bowl, combine the ricotta cheese with ¼ cup grated parmesan cheese, the dried oregano and a large pinch of salt and pepper. Set aside.
In a large skillet over medium-high heat, heat the 2 tablespoons of olive oil until hot. Add the garlic and cook, stirring, for 30 seconds. Do not let the garlic burn. Add the tomatoes, crushed red pepper, 1 teaspoon salt and ½ teaspoon pepper. Cook for 4 minutes, then add the reserved pasta water and spinach. Cook for another minute or two, or until the spinach has wilted. Add the tomato/spinach mixture to pasta and toss. Serve the pasta in large, shallow bowls with a dollop of the ricotta mixture in the center. Drizzle with a little olive oil and a grating of parmesan.