Cook mostaccioli and chicken according to package directions. Meanwhile, in a large bowl, combine the cheddar cheese, sour cream, ricotta, pesto, cream and Parmesan cheese.
Chop chicken tenders and drain mostaccioli; add to cheese mixture. Toss to coat. Transfer to two greased 11-in. x 7-in. baking dishes (dishes will be full). Combine bread crumbs and butter; sprinkle over the top.
Bake, uncovered, at 350° for 25-30 or until heated through and golden brown.