01 - Line a baking sheet with parchment paper and set aside.
02 - In a medium mixing bowl, combine the creamy peanut butter, Greek yogurt, maple syrup (or honey), and vanilla extract. Stir until the mixture is completely smooth and well blended.
03 - Using a spoon or small cookie scoop, drop heaping teaspoons of the filling onto the prepared baking sheet, spacing them slightly apart. You should get approximately 24 small mounds.
04 - Place the baking sheet in the freezer for at least 2 hours, or until the bites are completely firm and frozen solid.
05 - About 10 minutes before the freezing time is up, place the chopped dark chocolate and coconut oil (if using) in a microwave-safe bowl. Microwave in 30-second intervals, stirring between each burst, until the chocolate is fully melted and smooth. Alternatively, melt using a double boiler.
06 - Remove the frozen bites from the freezer. Using a fork or dipping tool, dip each frozen bite into the melted chocolate, allowing any excess to drip off. Return each coated bite to the parchment-lined baking sheet.
07 - Immediately sprinkle the tops of each chocolate-coated bite with flaky sea salt before the chocolate begins to set.
08 - Return the baking sheet to the freezer for another 10–15 minutes, or until the chocolate coating is firm to the touch.
09 - Transfer the finished bites to an airtight container and store in the freezer for up to 1 month. Serve directly from the freezer or let sit for a few minutes to soften slightly.