In a blender, combine the unsweetened almond milk, cocoa powder, roasted hazelnuts, frozen banana, natural honey or maple syrup, vanilla extract, and salt. Blend on high until smooth and creamy.
Taste the smoothie and add ice cubes if a thicker consistency is desired. Blend again to incorporate the ice.
Pour the smoothie into serving glasses and garnish with chopped hazelnuts or cocoa nibs if desired. Serve immediately.
Notes
If you prefer a thinner consistency, add extra almond milk. Adjust the sweetness to taste and use freshly roasted hazelnuts for the best flavor.