Preheat oven to 400 degrees. Coat a 9 x 9-inch baking pan with cooking spray.
Heat oil in a medium, nonstick pan over medium-high. Add garlic and cook for 1 minute. Add spinach and stir until wilted. If using frozen, defrost and squeeze out liquid before adding to the pan. Transfer to a work surface, chop and set aside.
Cook onions in the microwave for 1 minute, to soften.
In a mixing bowl, combine 1 cup Alfredo sauce with chicken, spinach, and onions. Working with one crepe at a time, place each on a work surface. Spread a generous ½ cup chicken mixture down center of a crepe. Spread across the middle of the crepe. Roll into a cylinder. Transfer, seam-side down, to baking dish. Assemble the remaining 3 crepes and add to the baking dish. Spoon 2 tablespoons Alfredo sauce on top of each and sprinkle each with 2 tablespoons mozzarella cheese. Finally, sprinkle each with 1 teaspoon Parmesan cheese.
Bake, uncovered, for about 15 minutes until hot and cheese is melted. Remove from the oven and let cool slightly. Sprinkle with chives or scallions, if desired.