Add <quantity>80<unit>g</unit></quantity> of powdered sugar and <quantity>50<unit>g</unit></quantity> of cocoa powder into a bowl. Whisk to combine

Add <quantity>60<unit>g</unit></quantity> of egg whites and the melted butter. Whisk until homogeneous

Spread the dough in a thin layer on a baking mat with an offset spatula. If you do not have a baking mat, use a sheet of parchment with a small amount of cooking spray. Sprinkle with sesame seeds to taste

Transfer the baking mat to a baking tray. Bake in a preheated oven at <temperature>170<unit>°C</unit></temperature> for 7m until crispy. The cocoa & sesame tuile is ready

Beat <quantity>70<unit>g</unit></quantity> of white sugar and <quantity>90<unit>g</unit></quantity> of egg yolks until the mixture is fluffy and pale yellow

Add <quantity>300<unit>ml</unit></quantity> of heavy cream and <quantity>300<unit>ml</unit></quantity> of milk to a pan over medium heat

Add <quantity>15<unit>g</unit></quantity> of instant coffee and mix until dissolved

Pour half of the coffee mixture over the egg yolks and sugar mixture. Whisk to combine

Transfer to a pan and add the other half of the coffee mixture. Stir constantly over low heat until it thickens. Do not let it boil

Add <quantity>250<unit>g</unit></quantity> of 50% cocoa chocolate chunks and mix until fully incorporated

Let the custard cool down to <temperature>60<unit>°C</unit></temperature> an add <quantity>3<unit>leaves</unit></quantity> of gelatin. Whisk to dissolve

Transfer to a clean bowl and cover it with cling film, pressing lightly against the surface

Place in the refrigerator for 2h until completely chilled

Remove from the refrigerator and beat until the mixture is smooth

Whip <quantity>600<unit>g</unit></quantity> of heavy cream until it becomes firm

Add ⅓ of the whipped cream to the coffee custard using a spatula. Make upward movements to incorporate the cream. Add the other ⅔ in 2 parts

Cover the bowl with cling film and refrigerate it for 8h until it sets

Serve the mousse in a plate. The coffee mousse is ready

Enjoy it with a cocoa & sesame tuile!