Preheat oven to 200 degrees. Line 2 baking sheets with a non-stick liner. In the bowl of an electric mixer, beat the egg whites until they hold soft peaks. Slowly add the confectioners' sugar and beat for 10 to 12 minutes, until they are firm. Add the Grand Marnier, to taste.
Drop tablespoon amounts of batter onto the baking sheets, leaving 3-inches of space between each. Using the back of the spoon, smooth each meringue into a flat disk. Bake for 2 to 2 1/4 hours until meringues can be easily lifted off the liners and are completely dried out.
Mascarpone Cream: Combine the mascarpone, cream, sugar, and orange liqueur, and whip until they hold soft peaks. Cover and refrigerate until ready to use. Place meringue disc on plate and top with macerated strawberries and dollop of cream, repeat. Finish with meringue top.