Put 4 of the blackberries in cocktail shaker and using a muddler, mash the blackberries. Add crushed ice, lemon juice, gin, simple syrup, Creme de Mure blackberry liqueur to the shaker. Shake for a minute or so and then pour (I don't strain) into cocktail glass. Garnish with orange peel and a couple of the fresh blackberries.
Recipe Notes
If too strong for you, add a splash of something sparkling. Sit back and enjoy.