Bring a large pot of salted water to a boil. Add the orzo pasta and cook according to package instructions until al dente, about 8-10. Drain and rinse under cold water.
In a food processor, combine basil, pine nuts, nutritional yeast, garlic, lemon juice, salt, and pepper. Pulse until finely chopped. With the processor running, drizzle in olive oil until smooth.
In a large bowl, combine cooled orzo with the pesto. Toss to coat the pasta evenly.
Add sun-dried tomatoes, cherry tomatoes, red onion, and parsley. Gently fold together and season to taste. Chill for at least 30 before serving.