Prepare the rolled biscuit:

Preheat the oven to 180°C and line a baking tray with baking paper.

Separate the egg whites from the yolks. Beat the yolks with the sugar until the mixture turns pale. Stir in the cornstarch, almond flour, and a teaspoon of dissolved coffee.

Whisk the egg whites until stiff peaks form, adding a pinch of salt. Gently fold them into the previous mixture.

Spread the dough on the baking sheet and bake for 10 to 12 minutes, until the biscuit is lightly golden.

Remove the biscuit from the oven and immediately turn it out onto a clean, damp tea towel. Carefully peel off the baking paper and roll the biscuit up in the tea towel. Let it cool.

Prepare the filling:

Melt the chopped white chocolate in a double boiler or in the microwave. Add the mascarpone and a teaspoon of coffee, then mix until you have a smooth ganache. Let it cool to room temperature.

Let the ganache cool.

Assemble the log:

Carefully unroll the biscuit and spread an even layer of white chocolate and coffee ganache. Sprinkle with crushed pecans.

Roll the biscuit up tightly, then coat it with the remaining mascarpone-white chocolate ganache. Refrigerate for at least 2 hours to allow the log to set completely.

Decorate the log:

After an hour, when the ganache has firmed up but is still soft, you can use a fork to score the log. Then decorate with a few pecans.

For an extra touch, you can add a few drops of diluted coffee to the surface to intensify the flavors.