Pre-heat the oven to 350 degrees. Cook pasta shells according to package directions. Drain and set aside. In a large skillet over medium heat brown ground turkey until no longer pink. Drain any excess fat. Stir in onion, oregano, basil, and cumin. Stir in 1 can of the enchilada sauce. Stir in refried beans. Set aside.
Fill each cooked pasta shell with the turkey/refried bean mixture. Coat an 11 x 7-inch baking dish with nonstick cooking spray and pour half of the remaining can of enchilada sauce evenly over the bottom. Place each shell into the bottom of the dish. Pour the remaining enchilada sauce over the tops of the shells.
Cover and bake at 350 degrees for 25 minutes. During the last few minutes of cooking, uncover and sprinkle the tops of the shells with Colby-jack cheese. Bake until the cheese has melted.