Preheat oven to 425 degrees F. Place puff pastry on a cookie sheet. Cut a circle out of the pastry center and place to the side on same cookie sheet. Sprinkle 1 tablespoon of sugar over puff pastry. Bake pastry until it rises and sugar is caramelized.
In a small saute pan, place butter, remaining sugar, and strawberries over medium heat. When strawberries begin to soften, slowly add Grand Marnier. (Note: Grand Marnier is flammable.)
Remove puff pastry from oven and place on a plate. Pour strawberries over pastry and place a dollop of whipped cream over center. Place circle of puff pastry on top of whipped cream. Serve garnished with sprig of mint.