Bring a small pot of water to a rolling boil, then add the shelled unsalted pistachios. Blanch them for about 1 minute.

Using a fine-mesh sieve, drain the blanched pistachios and transfer them to a bowl of ice water. Rinse to halt cooking.

Peel the pistachios by pinching off the skins; use a kitchen towel for grip if needed.

Spread the peeled pistachios on a clean kitchen towel and pat them dry.

Place the dried pistachios into a food processor and pulse until they are in fine crumbs.

Add the granulated sugar and softened unsalted butter to the food processor; pulse until combined.

Gradually add whole milk while processing until you achieve a thick, smooth paste.

Transfer the pistachio paste into a mixing bowl. Add cold heavy cream, milk, vanilla extract, and sea salt; fold until combined.

Using an electric mixer, beat the mixture on medium-high speed until stiff peaks form, about 2-4 minutes.

Taste the pistachio cream and adjust sweetness or flavor as desired.

Consider refrigerating the pistachio cream for at least 30 minutes before serving.