Begin by heating 1 cup of heavy whipping cream in a small saucepan over medium heat until just simmering.

Stir in 1 cup of shelled, peeled unsalted pistachios, allowing them to infuse for about 15 minutes.

Strain the mixture through a fine sieve to remove the pistachios, then return the cream to the pan.

Add 8 ounces of finely chopped white chocolate and stir until melted and smooth.

Set aside to cool and thicken.

Start by separating 4 large eggs and letting the egg whites age in the refrigerator for at least 24 hours.

In a mixing bowl, whip the aged egg whites with a pinch of cream of tartar until foamy and soft peaks form.

Gradually add 1 cup of granulated sugar, beating until stiff peaks are achieved.

Sift together 1 cup of superfine almond flour, 1 cup of powdered sugar, and ¼ cup of pistachio flour into the whipped egg whites.

Gently fold the dry ingredients into the meringue using a spatula.

Aim for a thick, smooth batter that ribbons off the spatula without breaking.

Prepare your baking sheets with parchment paper or a silicone baking mat.

Transfer the macaron batter into a piping bag fitted with a round tip.

Pipe 1 ½-inch circles onto the sheets, leaving space between each.

Tap the sheet gently on the countertop to release any air bubbles.

Let the shells rest for about 30 minutes until a skin forms on the surface.

Preheat your oven to 315°F (157°C).

Bake the rested pistachio macaron shells for 18-21 minutes, rotating the trays halfway through.

The shells are done when they easily lift off the parchment without cracking.

Once the macaron shells are cool, retrieve your cooled pistachio ganache and give it a good stir.

Pipe a generous dollop of ganache onto the flat side of one macaron shell and gently press another shell on top.

Refrigerate the macarons overnight to allow their flavors to mature.