WHIRL milk and dark chocolate in a food processor until finely chopped. Bring cream just to a boil in a small saucepan over medium-high. Pour over chocolate. Add vanilla and pulse until smooth. Add butter, 1 piece at a time, and drizzle in whisky through feed tube, with motor running. Scrape into a small bowl. Refrigerate, covered, until firm, at least 1 ½ hours or up to 3 days.
LINE a tray or baking sheet with wax or parchment. Scoop a scant 1 tbsp of chocolate mixture and roll into a ball. Place on tray. Repeat with remaining mixture. Freeze balls until firm, at least 20 min.
MELT white chocolate in a microwave-safe bowl with coconut oil on medium, stirring every 20 sec, until smooth. Using a fork, dip truffles into melted chocolate, shaking off excess, and set on waxed paper. Immediately sprinkle tops with salt and pepper. Refrigerate until firm. Keep refrigerated in an airtight container, for up to 1 week.