You may be put off with the addition of mayonnaise, like I was in the beginning. Let me tell you, it adds a distinct creaminess that can't be found otherwise.
This meal is a pleasant surprise and you'll be reaching for seconds quickly.
1 package (12 ounces) shells and cheese dinner mix
1/4 cup chopped onion
4 tablespoons butter, divided
2 cups cubed cooked chicken
1 package (10 ounces) frozen peas, thawed
2/3 cup mayonnaise
1/3 cup seasoned bread crumbs
Prepare dinner mix according to package directions. Meanwhile, in a small skillet, saute onion in 2 tablespoons butter until tender. Stir the chicken, peas, mayonnaise and sauteed onion into dinner mix.
Transfer to a greased 1-1/2-qt. baking dish. Melt remaining butter; toss with bread crumbs. Sprinkle over top. Bake, uncovered, at 350° for 20-25 minutes or until bubbly.