1In Dutch oven, heat water, 1 can of the evaporated milk, the salt, garlic and pasta to simmering over medium heat. Simmer 12 to 14 minutes, stirring frequently, until pasta is tender.
2In medium bowl, beat remaining can of evaporated milk and the cornstarch; stir in chicken and artichoke hearts. Add to mixture in Dutch oven; return to simmering, and continue to simmer 1 to 3 minutes or until thickened and mixture coats back of spoon.
3Remove from heat; stir in half of the cheese and the lemon juice. Stir until cheese melts, then add remaining cheese (reserving 1/4 cup for serving, if desired) and butter; stir again.
4Add spinach, and stir until wilted. Serve with reserved cheese and pepper.