Step 1

Toast the pistachios (either in the oven or stovetop will work) and chop them roughly.

Step 2

Combine double cream with 1 cup chopped pistachios; mix then set aside in the refrigerator for at least 30 minutes.

Step 3

Take the cream with pistachios from the refrigerator and strain the pistachios. Set it aside.

Step 4

Add vanilla extract into the cream and whip it to combine.

Step 5

In a separate medium-sized bowl, beat the egg whites while slowly adding the sugar -- continue beating until the egg whites become stiff and glossy.

Step 6

Gently fold 1/3 of the egg whites into the whipped cream; repeat until all the egg whites have been combined with the cream.

Step 7

Add the strained pistachios and mix gently.

Step 8

Spoon into your molds or tin. Cover the tins with plastic wrap.

Step 9

Place tins or molds in the freezer for at least 4 hours.

Step 10

Remove your pistachio semifreddo from the tin and sprinkle with the remaining chopped pistachios.

Step 11

Serve.