Remove and discard giblets and neck from turkey. Rinse turkey with cold water; pat dry. Trim excess fat. Starting at neck cavity, loosen skin from breast and drumsticks by inserting fingers, gently pushing between skin and meat.
Combine cumin and next 5 ingredients (cumin through turmeric) in a bowl. Rub cumin mixture under loosened skin and inside body cavity. Tie ends of legs with cord. Lift wing tips up and over back; tuck under turkey.
Place turkey on a broiler pan coated with cooking spray or on a rack set in a shallow roasting pan. Insert meat thermometer into meaty part of thigh, making sure not to touch bone. Bake at 350° for 3 hours or until thermometer registers 180°. (Cover turkey loosely with foil if it gets too brown.)
Combine boiling water and chipotle chiles in a small bowl; cover and let stand 30 minutes or until soft. Drain, discarding stems, seeds, and membranes. Combine chiles and 1/2 cup broth in a blender, and process until smooth. Set aside.
Remove turkey from oven. Cover turkey loosely with foil; let stand at least 10 minutes before carving. Place a zip-top plastic bag inside a 2-cup glass measure. Pour drippings into bag; let stand 10 minutes (fat will rise to the top). Seal bag, and carefully snip off 1 bottom corner of bag. Drain drippings into a medium saucepan, stopping before fat layer reaches opening; discard fat. Add 3 cups broth to drippings. Bring to a boil; cook until reduced to 3 cups (about 6 minutes). Stir in chile mixture, tomato paste, and Worcestershire sauce. Combine 1/4 cup broth and flour in a small bowl, stirring with a whisk, and add to chile mixture in saucepan. Bring to a boil; reduce heat, and simmer for 10 minutes. Strain mixture through a sieve over a bowl, and discard solids. Serve sauce with turkey. Garnish with fresh chiles and herbs, if desired.