Shredded Parmesan and fresh basil leaves, optional
Combine alfredo sauce and pesto in medium-sized bowl. Set aside.
Select saute setting on a 6-qt. electric pressure cooker and adjust for medium heat; add 1 tablespoon oil. When oil is hot, add chicken; season with salt and pepper. Cook and stir until lightly browned, 3-4 minutes. Add onion; cook and stir until tender, 2-3 minutes. Press cancel.
Layer mushrooms, broccoli, cauliflower and reserved sauce into pressure cooker. Lock lid; close pressure-release valve. Adjust to pressure-cook on high for 10 minutes. Let pressure release naturally for 3 minutes; quick-release any remaining pressure.
Stir to combine. If desired, top with Parmesan and basil leaves.