In a large heavy skillet cook bacon over moderate heat until crisp and with a slotted spatula transfer to a cutting board. Chop bacon fine. Remove all but 1 tablespoon fat from skillet and heat remaining fat over moderately high heat until hot but not smoking. Cook chard and garlic, stirring, until chard is tender, about 2 minutes. Transfer chard mixture to a bowl and cool. To chard mixture add cheeses, 2 tablespoons bacon, and salt and pepper to taste.
Bring a large saucepan of salted water to a gentle boil.
Put a won ton wrapper on a lightly floured surface and mound 1 tablespoon filling in center of wrapper. Brush edges of wrapper with water and put a second wrapper over first, pressing down around filling to force out air. Seal edges well and transfer ravioli to a kitchen towel. Make more ravioli with remaining wrappers and filling in same manner, turning them occasionally to dry slightly. Cook ravioli in water at a gentle boil 6 to 8 minutes, or until they rise to surface and are tender. (Do not let water boil vigorously once ravioli have been added.) With a slotted spoon transfer ravioli as cooked to a kitchen towel to drain.
Divide ravioli between 2 plates and spoon sauce over them. Garnish ravioli with remaining tablespoon bacon.
