Makes: 12 servings. Prep: 15 minutes. Cook: about 20 minutes. Bake: at 350° for 30 minutes.
Heat oven to 350°F. Coat 13 x 9 x 2-inch baking dish with cooking spray.
Cook shells in lightly salted boiling water for 13 minutes, following package directions. Drain.
In large heavy-bottomed saucepan (not nonstick), melt butter over medium heat. Stir in flour until well blended; cook for 1 minute. Whisk in 1 cup half-and-half; cook, whisking continuously, until very smooth. Whisk in remaining 1 cup half-and-half; continue to cook, whisking until thickened and smooth, about 6 minutes. Remove from heat. Stir in Chipotle Seasoning, salt, 1 cup of Jack cheese and 1 cup of cheddar cheese until smooth.
Stir ham and cheese sauce into pasta. Spoon into prepared dish. Top with remaining cheeses.
Bake in 350°F oven until bubbly and lightly golden on top, about 30 minutes. Remove from oven to rack; let stand 10 minutes before serving.