Greek Yogurt Chocolate Mousse

Add the chopped chocolate to a microwave-safe bowl. Microwave the chocolate on high for 1 minute, then stir. If not completely melted, microwave for 30 more seconds, then stir until all chunks are melted. If it is still not melted, microwave another 30 seconds and continue to stir, just until the chunks in the chocolate are melted. Do not overcook. In a medium mixing bowl, whip the Greek yogurt with an electric mixer until fluffy. Add the stevia, vanilla, and milk, and beat some more, then add the chocolate, a small amount at a time, beating in between additions. Once all of the chocolate is mixed into the yogurt, divide the mousse into 6 portions and top each portion with 2 tablespoons whipped topping.