1-How to Prepare the Perfect Pistachio Eclairs: Let’s dive into the fun part actually making these pistachio eclairs! Start by preheating your oven to 375°F, as that’s the key temp for those perfect pastry shells. You’ll combine 1 cup water, ½ cup unsalted butter, 1 tablespoon sugar, and ¼ teaspoon salt in a saucepan and bring it to a boil, then stir in 1 cup all-purpose flour all at once.

2-Once the dough forms a ball, cool it slightly before beating in 4-5 large eggs one at a time until it’s smooth and shiny. Pipe the dough into strips and bake for 30-35 minutes until golden, then slit the shells to release steam for the last 5 minutes. While that’s happening, prepare the mousse by pulsing ¼ cup unsalted roasted pistachios, heating 1 cup milk with them, and steeping for an hour before straining.

3-For the mousse, bloom 1 teaspoon gelatin powder in water, mix it with the milk, and cook a custard with 2 egg yolks, 2 tablespoons sugar, and ¼ teaspoon salt to 180°F. Pour this over 150 grams chopped white chocolate, blend smooth, add 25 grams pistachio paste, and fold in whipped ¼ cup cold heavy whipping cream. Finally, for the glaze, melt 3 oz chopped white chocolate with 2 tablespoons heavy whipping cream.

4-Filling and Assembling: Once everything’s ready, pipe the mousse into the cooled shells through holes on the bottom, then dip them in the glaze. Let it set, and you’re good to go! Preheat your oven to 400°F (200°C) as in the initial steps, combine water and butter, and boil for the choux base it’s that simple. For vegan swaps, use flaxseed for eggs here to keep things light and airy.