I've used a blender as well but I prefer the consistency that comes from the food processor. Up to you.If the bananas are not pulsing well, add a tablespoon or so of coconut milk or other milk or cream. If you let the bananas defrost for a few minutes it will be easier to pulse and you probably won't need the added milk.To counteract any bitterness from the tahini, add a teaspoon or so of maple syrup, honey, a softened date, or date purée while pulsing the bananas and tahini.