Add cream, dulce de leche and vanilla extract into a large mixing bowl and whip to stiff peaks using a hand mixer. Add bananas and continue whisking until well combined.
Transfer cream mixture to a flat baking dish. Freeze for at least 2-3 hrs.
When Ice Cream is ready use a 5cm round cookie cutter to cut rounds of the ice cream. Cut those in half and put back in the freezer
Add flour, sugar, cocoa powder and salt into a large mixing bowl. Whisk until well combined. Add egg whites, melted butter and vanilla extract and mix until well combined.
Add about 2 tbsp of the mixture into a well oiled, preheated ice cream cone waffle iron. Close lid and cook for 4 min on medium heat. As the iron gets hotter you may need to cook less or lower the heat setting.
As soon as the waffles are done, carefully take off the iron, add haf ice cream dsic on one side and fold over the other half forming the taco. Dipp the top into melted chocolate and sprinkle with nuts before serving.
Tacos can be made several days ahead of time and stored in an airtight container in the freezer.