Make Pistachio Butter: Place raw pistachios into a food processor and process on high for about 8–10 minutes until smooth.

Prepare Pudding Base: In a medium pot, combine granulated sugar and cornstarch, whisking thoroughly. Crack in the eggs and mix until smooth.

Combine Ingredients: Add pistachio butter to the pot and stir. Gradually pour in the milk while whisking to combine.

Cook the Pudding: Over medium heat, stir constantly until thick and bubbling, about 5–10 minutes.

Strain: Pour the pudding through a fine-mesh sieve into a bowl to ensure it's silky smooth.

Finish Off: While warm, whisk in unsalted butter and almond extract until melted and incorporated.

Chill: Cover with plastic wrap directly on the surface and refrigerate for at least 3 hours.