Place a large metal mixing bowl and metal beaters (or wire whisk from stand mixer) in your freezer for 20 to 30 minutes, or longer, until very chilled.
Pour the heavy cream into the chilled bowl and the powdered sugar. Beat with chilled beaters at a high speed until thick and creamy. This will take at least 5 minutes or more. Use a spoon to fold in 2 tablespoons of creme de menthe. Taste and add additional creme de menthe, if desired.
Serve with strawberries for dipping.
If substituting Cool Whip for the homemade whipped cream, omit the heavy cream and powdered sugar.