1. In a large bowl, mix together flour, baking powder, vanilla extract, salt, sugar, soy milk, and mashed banana, until a smooth dough forms.
2. Heat oil in a wide pot. Oil is ready for frying when the handle of a wooden spoon is inserted and tiny bubbles form around it.
3. Use an ice cream scoop or two tablespoons to form balls out of dough, and place carefully into hot oil.
4. Fry two to three minutes on each side until golden.
5. Remove from oil with a slatted spoon and place on paper towels.