In a large saucepan over medium heat, cook 2 cups of cream until just bubbling. Stir in chicken base and Asiago cheese. Stir with a whisk until dissolved. Add cornstarch mixture, and simmer until sauce is thickened, stirring constantly. Mix in the sun-dried tomatoes. Set aside for a few moments.
Bring a large pot of lightly salted water to a boil. Add pasta and cook for 8 to 10 minutes or until al dente, drain. Place bacon in a skillet and cook until evenly brown. Drain, crumble and set aside.
Melt butter in a large saucepan over medium heat. Sauté red onion until soft and translucent. Stir in garlic and cooked bacon, and cook for 2 minutes. Stir in green onions, chicken and 1 cup cream. Cook, stirring, until cream is heated through. Add Asiago cream sauce, and heat through. Toss with cooked pasta until evenly coated, and sprinkle with chopped parsley.