Make the keto simple syrup: Combine water and sweetener in a small saucepan. Heat and stir until dissolved.
Cool, then refrigerate. For a thicker texture, blend in xanthan gum after it cools.
Prep your glassware: Chill coupe or flute glasses for the Raspberry Keto 75, martini glasses for the Chocolate Martini, and tall Collins glasses for the Spritz.
Raspberry Keto 75: In a shaker, muddle the raspberries with lemon juice and keto syrup. Add gin and ice.
Shake 10–12 seconds, fine-strain into two chilled flutes, then top with very dry bubbles. Garnish with a lemon twist or a raspberry.
Creamy Keto Chocolate Martini: In a shaker, combine vodka, almond or coconut milk, cocoa (or sugar-free syrup), keto syrup, vanilla, and a pinch of salt. Add ice and shake hard for 15 seconds.
Strain into two chilled martini glasses. Garnish with a light cocoa dust or shaved sugar-free chocolate.
Ruby Citrus Spritz: In a shaker, combine vodka or gin, lime juice, grapefruit juice (or extract + water), and keto syrup. Add ice and shake briefly.
Strain into two ice-filled Collins glasses and top with sparkling water. Stir gently and garnish with a lime wheel and grapefruit twist.
Taste and tweak: Adjust sweetness with a touch more syrup, or acidity with a splash of lemon or lime, to suit your palate.