1. In a saucepan, bring 1/2 cup water to a boil. Stir in 15 mL (1 tbsp) of Caf-Lib and 30 mL (2 tbsp) of sugar. Remove from heat and let cool. Pour into a deep dish.
2. Using the electric mixer, whisk the egg yolks with the remaining sugar in a bowl until the mixture whitens. Add the mascarpone and whisk. Place half of the mixture in another bowl.
3. In one of the bowls, add 15 mL (1 tbsp) of Caf-Lib and cocoa. Whisk until the Caf-Lib is dissolved.
4. Using the electric mixer, whisk egg whites at high speed in a third bowl until stiff peaks are obtained.
5. Add half of the egg whites to the Caf-Lib mousse by carefully folding the mixture with a spatula.
6. Add the rest of the egg whites to the mascarpone mousse by carefully folding the mixture with a spatula.
7. Dip half of the cookies quickly in the liquid preparation prepared in step 1. Spread the cookies in the bottom of four small Mason jars.
8. Using a pastry bag, divide half of the Caf-Lib mousse into the jars. Spread half of the mascarpone mousse in the pots. Repeat with the remaining biscuits and mousses.
9. Garnish each serving with a pinch of Caf-Lib. Cover and refrigerate for 1 to 2 hours.