Place the vegetable broth into a saucepan, and bring to a boil. Stir in the pasta, and boil over medium-low heat until tender, about 8 minutes.
Drain pasta, and reserve broth.
Heat the butter in a skillet over medium heat, and stir in half the spring onions; cook and stir until the onions begin to soften, 2 to 3 minutes, then add the vegetarian chicken-style pieces. Cook until vegetarian pieces are browned, about 3 minutes per side, then stir in remaining onion and green peas.
Pour 1/2 cup of reserved vegetable broth into the skillet. Bring the mixture to a boil, cook for 1 to 2 minutes to cook the peas, and stir in the pasta and pesto sauce.
Mix in an additional 1/2 cup of broth to form a creamy sauce.
