Place pistachios in a food processor. Turn the food processor on and let it run on high for about 5 minutes, scraping down the sides with a spatula as necessary.
Add the honey, grapeseed oil and honey, and process until the mixture is smooth again, about 2-3 more minutes.
In a microwave, melt chocolate bar; stir until smooth.
Fill a regular muffin tin with paper liners. Drop about 2 tablespoonfuls of the melted chocolate into the muffin cups. Drop 2-3 teaspoonfuls of the pistachio butter into the center of each cup; top with the remaining melted chocolate, about 2 teaspoons for each cup.
Sprinkle each cup with a pinch of coarse sea salt.
Freeze until set, about 1 hour and then enjoy!