Meanwhile, slice green onions, using the white and light green part and discarding remaining. (You should have approximately 1 cup sliced onion.)
Break woody ends off asparagus and discard. Cut asparagus into 3/4-inch pieces, leaving tips of spears a little longer.
Sauté onions and asparagus in oil over medium heat for 2 to 3 minutes.
Add parsley and garlic and sauté for one additional minute.
Add water or broth, cover, and simmer until asparagus is tender-crisp (about 2 to 3 minutes).
Stir in peas, chives, and seasonings. Cook 1 to 2 minutes or until heated through and peas are tender. There will be extra broth leftover; don’t drain it.
Combine drained pasta, vegetable mixture (with broth), and lemon juice. Gently stir in dressing, using more or less depending on how saucy you like your pasta.
Serve immediately with lemon wedges and diced avocado as desired.