Although you only need one ingredient - heavy cream - for this recipe, most of us like a sweet whipped cream, because we're using it as a topping for pies, hot chocolate or ice cream. So I recommend adding 2-3 Tbsp. of powdered sugar to 2 cups of cream for the perfect amount of sweetness.
Don't have powdered sugar? Regular granulated sugar works fine, too. I don't recommend using honey or syrups to add sweetness to whipped cream. They will alter the texture too much. But a bit of lemon zest, orange zest or cocoa powder can add wonderful flavor and color to whipped cream.