1. Preheat the oven to 350°F (180°C).
2. In a bain-marie, melt the chocolate with the butter.
3. In a small bowl, mix the flour with the baking powder.
4. In another bowl, whisk eggs with the brown sugar. Stir in the chocolate mixture, then add the flour mixture.
5. Divide the batter evenly between two baking sheets lined with parchment paper. Garnish with one of the baking sheets with chocolate chips. Bake 10 minutes.
6. Remove from oven and let cool. Freeze 1 hour.
7. Cut mandarins, cherries and lychees into pieces. Refrigerate 30 minutes.
8. Divide the ice cream into three bowls. Let the ice cream soften slightly until it is spreadable.
9. Stir in mandarins, cherries and lychees separately in each bowl. Freeze for 1 to 2 hours until the ice cream is semi-firm.
10. On the cookie without the chocolate chips, divide the three kinds of ice cream separately forming three strips.
11. Cover with the cookie that has the chocolate chips. Freeze for 1 to 2 hours until the ice cream is firm.
12. Cut into 24 sandwiches.