SEASON chicken, if desired, with salt and pepper. Melt 1 tablespoon margarine in large nonstick skillet over medium-high heat and cook chicken, stirring occasionally, until chicken is thoroughly cooked, about 5 minutes. Remove and set aside.
MELT remaining 1 tablespoon margarine in same skillet over medium-high heat and cook mushrooms, stirring occasionally, until golden, about 3 minutes.
ADD 1 1/2 cups water, Knorr® Rice Sides™ - Garlic Parmesan, milk and peas to same skillet and bring to a boil. Reduce heat to medium-low and simmer covered, stirring occasionally, 7 minutes, or until rice is tender. Stir in chicken until heated through; now it's delicious. Dig in!