Preheat oven to 325 degrees. Generously butter an 8-inch springform pan; set aside. Bring a large pot of water to a boil; add salt and pasta. Cook pasta until almost al dente. Drain, rinse under cold running water, and drain again. Transfer to a large bowl, and stir in red pepper and spinach; set aside.
In another large bowl, stir to combine ricotta, eggs, basil, pecorino, garlic, and nutmeg; season with 1 teaspoon salt and pepper. Transfer to bowl with pasta, and gently stir until well combined. Transfer to prepared pan. Smooth top, and sprinkle with Parmesan. Bake until firm to the touch and the top is golden brown, 40 to 50 minutes. Let stand 10 minutes before unmolding, and serve warm or at room temperature.