Preheat your oil in a heavy-based pot for deep-frying to 365 degrees F.
In a large mixing bowl combine flour, cornstarch, baking powder, sugar, salt, and cinnamon. Make a well in the center and add the yolks and club soda. Using a whisk, stir from the inside working your way out, slowly incorporating the dry ingredients without forming any lumps. Peel the bananas and dip in the batter to coat well. Fry in hot oil for 4 to 5 minutes until batter is puffy and golden brown. Drain on paper towels.
While bananas are cooking, prepare caramel sauce. Combine the sugar and water in a large heavy saucepan over medium heat. Cook, swirling the pot around, until the mixture is a deep caramel color and looks like syrup, about 8 minutes. Add the butter then carefully pour in the cream (it will bubble up) and continue to cook for another minute. Add a pinch of salt and cool before serving.
To serve the banana split, cut the bananas lengthwise and top with a large scoop of vanilla bean ice cream. Pour warm caramel sauce over the top and finish with a sprinkle of banana chips and toasted pecans.