Banana Smoothie

Ingredients 
1 ripe banana 
1/2 c. nonfat yogurt 
1 tbsp. sugar (or to taste) 
1 tbsp. banana liqueur (optional) 
1 c. crushed ice 
1 tsp. fresh lime juice 
lime wedge or banana slice, for garnish 
Combine the first 6 ingredients in a blender and blend until smooth. 
Pour the smoothie into a large glass and garnish with a lime wedge or banana slice.