Preheat the oven to 350 degrees. Line a large baking sheet with parchment paper.

In a medium bowl, combine the cream cheese, powdered sugar, and Nutella. Mix until well blended.

Arrange 20 of the wonton wrappers on the prepared pan. Spoon 1 about teaspoon of the Nutella mixture onto the center of each wrapper. Use water-moistened fingers to wet the edges of the wrappers. Place a second wonton wrapper over the filling and press out as much air as possible while sealing the edges. Brush the melted butter all over the top of the ravioli. Use your fingers to ensure the butter-coated ravioli are sealed around the edges.

Bake for 10 to 14 minutes, until the wontons are golden brown. Cool for at least 10 minutes before drizzling the chocolate over top.

Melt the chocolate in a double boiler, or in a bowl over a saucepan of simmering water, or in the microwave, checking and stirring every 20 seconds. Use a fork to drizzle the chocolate over the baked ravioli and cool until set. You can also spoon the chocolate into a freezer bag, snip the end and pipe the chocolate onto the ravioli. Store leftovers in an airtight container, in the refrigerator, for up to 2 days.