chop shallots and garlic
slice mushrooms
cook mushrooms, shallots and garlic in pan till carmelized and remove from pan
coat chicken with 1/2 of cornstarch fry in pan 5 minutes each side
add mushrooms, shallots and garlic to chicken and add all liquid
simmer for 30 minutes
remove some liquid and mix with corn starch add back to pan to thicken cook another 10 minutes