Cook frozen cauliflower as directed on package. Place cooked cauliflower in food processor. Cover; process until smooth, scraping down sides of bowl as necessary. Set aside.
In 2-quart heavy saucepan, stir hot water, 1 1/2 cups milk, 2 tablespoons of the butter, and the sauce mix and uncooked pasta (from Chicken Helper box). Heat just to boiling, stirring frequently. Reduce heat; simmer uncovered about 10 minutes, stirring occasionally, until pasta is tender. Add cauliflower and frozen peas to pasta. Cook 2 minutes longer. Keep warm.
Cut each chicken breast into 3 to 5 slices, holding knife at an angle. (Slices should be about 1/2 inch thick.) Place chicken in medium bowl or food-storage plastic bag. Pour 1 tablespoon milk over chicken to moisten. Add seasoned crumbs (from Chicken Helper box); coat chicken with crumbs.
In 10- or 12-inch nonstick skillet, heat remaining 2 tablespoons butter and the oil over medium heat until butter is melted. Carefully add chicken; cook 4 to 6 minutes or until golden brown on bottom. Reduce heat to medium-low. Turn chicken; cook 4 to 6 minutes longer or until golden brown and no longer pink in center. Serve with pasta.