Bring a large pot of salted water to a boil and cook farfalle according to package directions.
Heat olive oil in a large frying pan over medium-high heat. Add onions and saute for 2 minutes or until they begin to soften. Add garlic and saute for 30 seconds or until fragrant.
Add chicken stock and bring to a boil; continue boiling for 6 minutes or until liquid has reduced and thickened slightly.
Remove tough ends from asparagus and cut into 1 inch pieces. Add to pan and cook 3 minutes or until almost tender crisp. Add peas, spinach, cooked chicken and lemon zest, and cook 2 more minutes or until peas are cooked and chicken is warmed.
Drain pasta and add to frying pan. toss pasta with sauce; sprinkle in parmesan and basil, stirring until combined. Season with salt and pepper to taste.