In a large skillet over medium heat, cook and stir spinach in batches until wilted, 3-4 minutes. Drain on paper towels. In a bowl, combine spinach with next 5 ingredients., In a small saucepan, melt butter over medium heat. Stir in flour until smooth; gradually whisk in milk. Bring to a boil, stirring constantly, until sauce thickens and coats a spoon, 2-3 minutes. Stir into spinach mixture., Place 1 tablespoon spinach mixture in center of a pot sticker wrapper. (Cover remaining wrappers with a damp paper towel until ready to use.) Moisten wrapper edges with water, and place another wrapper on top. Press edges to seal. Repeat with remaining wrappers., Fill a Dutch oven two-thirds full with water; bring to a boil. Reduce heat; drop ravioli in batches into simmering water until cooked through, 3-4 minutes. If desired, sprinkle with additional dill. Serve with sauce of choice., Freeze option: Cover and freeze uncooked ravioli on waxed paper-lined baking sheets until firm. Transfer to freezer containers; return to freezer. To use, cook as directed, increasing time to 6 minutes.