The original Manuel Wouters recipe uses lime, instead of lemon. And cane sugar.
Fill up the glass with crushed ice.

My personal stronger and more sour version of this cocktail:
60 ml Vodka
10 ml Violet sugar syrup
60 ml Lime juice (freshly squeezed)
10 fresh Raspberries
10 ml Sugar syrup 'rich' (2 sugar to 1 water, 65.0°Brix)
1 tea spoon cane sugar