Chill ingredients (optional but ideal): For the creamiest, frothiest result, refrigerate coconut milk and heavy cream for 30 minutes before blending — this helps the shake stay cold longer.
Blend base: In a blender, combine coconut milk, heavy cream, powdered sweetener, vanilla extract, and ground cardamom. Blend on medium-high for about 20–30 seconds until smooth and creamy.
Add ice & blend carefully: Add the ice cubes, then pulse 2–3 times — just until ice is crushed. Avoid over-blending, or the shake may become watery.
Pour & garnish: Pour into a chilled glass and, if desired, top with a dollop of sugar-free whipped cream, a light dusting of cinnamon or cardamom, or a sprinkle of crushed pistachios for a little crunch and colour contrast.
Serve immediately: Sip while cold for maximum creaminess and flavor.