Preheat oven to 350°.
Place a medium saucepan coated with cooking spray over medium heat until hot; add bell pepper and onion. Sauté 3 minutes or until tender. Lightly spoon flour into a dry measuring cup; level with a knife. Combine flour, coriander, and black pepper in a medium bowl; gradually add broth, stirring with a whisk until well-blended. Add to saucepan; bring to a boil, and cook 3 minutes or until thick, stirring frequently. Remove from heat; stir in cheese and sour cream. Combine 1 cup cheese mixture, turkey, and salsa in a bowl.
Spread 1/2 cup turkey mixture down center of each tortilla; roll up. Place in a 13 x 9-inch baking dish coated with cooking spray. Pour remaining cheese mixture over tortillas. Bake at 350° for 20 minutes or until bubbly.