Whisk together all ingredients for sauce, set aside.
Heat a large non-stick skillet over medium-high heat. Add the mushrooms and sauté until they have released their water and the pan is dry, about 5 to 10 minutes. Remove mushrooms from pan.
Return pan to heat and add one tablespoon of canola oil. Add the chicken and season with salt and pepper. Cook, stirring often, until chicken is cooked through. Remove chicken from pan.
Wipe out pan if needed. Return pan to heat and add the other tablespoon of canola oil. Add the onion and sauté for about 5 minutes, until softened and starting to turn golden.
Add the mushrooms and the chicken back to the pan, cook for about 3 minutes, until starting to brown.
Add the asparagus and cook for 1 to 2 minutes, until turning bright green.
Add the sauce and stir until everything is coated and sauce has thickened, about 1 minute.
Serve over rice if desired.
