Begin cooking the pasta. Heat the oil in a large skillet. Sauté the garlic and bell pepper over moderate heat until the garlic is lightly golden and the bell pepper is slightly wilted; about 3 to 4 minutes.
Add spinach, plum tomatoes, chickpeas, sun-dried tomatoes (and soaking liquid if you used dry sun-dried tomatoes), and oregano. Stir together and simmer gently for 8 to 10 minutes.
When pasta is done, drain it and transfer it to a large serving container. Toss in the vegetable and chickpea mixture. Season to taste with salt and black pepper and red pepper flakes. Toss again and serve, topping with Parmesan.