Lightly grease a 3-quart rectangular baking dish; set aside. For sauce, in medium saucepan combine tomatoes, the water, sweet onion, chipotle pepper, adobo sauce (if desired), cilantro, cumin, chili powder, and half of the salt. Bring to boiling; reduce heat. Simmer, uncovered, for 15 minutes; cool slightly. Transfer to a blender or food processor. Cover and blend or process until smooth.
For filling, in a large skillet cook and stir chicken in hot oil over medium-high heat until no longer pink. Drain off fat. Stir in salsa, sour cream, lime peel, and the remaining salt.
To assemble enchiladas, spread 1/2 cup of the sauce in the bottom of the prepared baking dish. Spoon about 3 tablespoons of the filling onto each tortilla near an edge; roll up tortilla. Place enchiladas, seam sides down, on top of sauce in dish. (To serve today, spoon the remaining sauce over enchiladas. Cover baking dish with foil. Omit Steps 4 and 5. Continue as directed in Step 6.)
Cover baking dish with foil. Transfer the remaining sauce to an airtight container; cover. Chill enchiladas and the remaining sauce for 2 to 24 hours.
To serve, let enchiladas and the remaining sauce stand at room temperature for 30 minutes. Spoon the remaining sauce over enchiladas. Re-cover baking dish with foil.
Preheat oven to 375 degrees F. Bake for 15 minutes. Sprinkle with cheese. Bake, uncovered, for 10 to 15 minutes more or until heated through. Sprinkle with green onions and olives.