Pat dry the strawberries.
Combine sugar, Grand Marnier, and orange zest in a large bowl. Stir until the sugar dissolves.
Add the strawberries; stir gently to coat.
Cover and chill 2 hours, stirring every 30 minutes.
Spoon strawberries into ramekins or dessert glasses.
Pour a little of the syrup from the strawberries over the top.
In a cold bowl, whip the whipping cream at high speed of an electric mixer until soft peaks form, adding the Tablespoon of sugar gradually. Top the strawberries with the whip cream and serve.