Place the garbanzo beans into a large container and cover with several inches of cool water; let stand 8 hours to overnight. Or, bring the beans and water to a boil in a large pot over high heat. Once boiling, turn off the heat, cover, and let stand 1 hour. Drain and rinse before using.
Heat olive oil in a large skillet or Dutch oven over medium-high heat, then stir in the sausage. Cook and stir until the sausage is evenly browned and no longer pink. Remove sausage and set aside, leaving any grease from the sausage in the skillet. Return the skillet to the stove and reduce the heat to medium, then add the bell pepper and onion. Cook and stir until the onion has softened and turned translucent, about 5 minutes; stir in the garlic. Continue cooking and stirring until the onion is golden brown, about 5 more minutes.
Reduce heat to medium-low. Stir in the flour until the mixture becomes paste-like and light golden brown, about 5 minutes. Gradually stir the tomatoes and chicken stock into the flour mixture, and bring to a simmer over medium heat. Cook and stir until the mixture is thick and smooth, 10 to 15 minutes. Season with basil, parsley, red pepper flakes, salt, and pepper. Stir in the sausage. Cover and cook over low heat for 2 hours, then add the prepared garbanzo beans. Cook for an additional hour.
Meanwhile, fill a large pot with lightly salted water and bring to a rolling boil over high heat. Once the water is boiling, stir in the pipette pasta, and return to a boil. Cook the pasta uncovered, stirring occasionally, until the pasta has cooked through, but is still firm to the bite, about 8 minutes. Drain well in a colander set in the sink. Stir the pasta into the stew, adding more chicken stock, if necessary.
