Ingredients :

• Butter — You need ‘beurre pommade’ — not melted, not cold, really soft, like cream. This is the foundation of the cookie’s texture. Use butter with at least 82% fat. Quality butter really changes the final taste.
• Icing sugar — No granulated sugar here. Icing sugar gives a finer, more melt-in-the-mouth texture to the dough. The supermarket kind works just fine.
• La Mancha pistachios — The original recipe mentions La Maison de la Pistache, and honestly, it’s a great reference. Spanish pistachios from La Mancha have a more intense flavor than common Iranian pistachios. If you can’t find them, get high-quality unsalted pistachios and crush them yourself.
• White couverture chocolate — The word ‘couverture’ matters. It’s a chocolate with more cocoa butter, which melts better and sets with a beautiful shine. Avoid basic supermarket bars for glazing — the result would be dull and pasty. Valrhona or Barry work perfectly.