Preheat oven to 325°. In a large skillet, cook sausage and onion over medium heat for 6-8 minutes or until sausage is no longer pink, breaking up sausage into crumbles; drain., In a large saucepan, bring water and salt to a boil. Slowly stir in grits. Reduce heat to medium-low; cook, covered, about 5 minutes or until thickened, stirring occasionally. Remove from heat., Add green chiles, 3/4 cup cheddar cheese, 3/4 cup Monterey Jack cheese, butter and pepper sauce; stir until cheese is melted. Stir in eggs, then sausage mixture., Transfer to a greased 13x9-in. baking dish. Top with remaining cheeses; sprinkle with paprika. Bake, uncovered, until golden brown and set, 50-60 minutes. Let stand 10 minutes before serving. Sprinkle with cilantro.