Prepare the ingredients.
Chop the onion.Slice the mushrooms.Julienne garlic cloves.
Pre-heat the pot and add oil. Season chicken with salt and pepper.
Brown chicken for 3 minutes per side. Set aside. Cook mushrooms, onions and garlic for 5 minutes.
Add stock, wine and mustard. Return chicken to pot. Stir well to combine.
Pressure Cooking Time: 8 min.
Remove chicken and simmer sauce for 2 minutes and then whisk in sour cream.