Preheat oven to 350F. Chop chipotles. Melt butter in a 3- to 4-quart saucepan over moderate heat, then add flour and cook, whisking, 1 minute. Gradually whisk in milk, cream, and mustard and simmer, whisking occasionally, 3 minutes. Cook macaroni in a 6- to 7-quart pot of boiling salted water until just tender.
Drain in a colander and transfer to a large bowl. Stir in white sauce, cheese, chipotles, and salt to taste. Spoon macaroni into two 1-quart shallow casseroles and sprinkle both with bread crumbs. Bake casseroles in middle of oven 30 minutes, or until bubbly.
at 12:00 AM on Jul. 26, 2009