• Preheat oven to 375°F (190°C) and line two baking sheets with parchment paper or silpat.
• In a large bowl, combine the flours, baking soda, baking powder, cinnamon, ginger and salt. Set aside.
• In the bowl of a stand mixer fitted with the paddle attachment, add in the butter and coconut sugar, beating until slightly pale and fluffy, around 2-3 minutes. Pour in the rest of the liquid ingredients and beat on medium high speed until fully incorporated. Slowly add in the flour mixture and beat until a dough forms.
• Using an ice cream scooper, transfer scoops of dough to the lined baking sheets, spacing them about an inch a part. Flatten each dough ball and sprinkle with some sparkling sugar. Place in the oven and bake for 6-8 minutes or longer if you want a crispier cookie. Leave to cool completely.
• Meanwhile, process the frozen bananas in a food processor until creamy and resembles soft-serve ice cream. (if the ice cream is melting too fast, just place in the freezer for about 5 minutes).

Assembly

• Immediately spoon the ice cream on to each cookie then place a cookie over the ice cream, pressing down gently to form a sandwich. Serve immediately or wrap each sandwich in cling wrap and place in the freezer for future snacking.