01 - Line a baking sheet with parchment paper and set aside for later use.
02 - Combine peanut butter, softened butter, powdered sugar, and vanilla extract in a mixing bowl. Mix thoroughly until completely smooth and uniformly blended.
03 - Roll the mixture between two sheets of parchment paper to approximately 1/2-inch thickness. Use a small heart-shaped cookie cutter to cut out hearts and arrange on the prepared baking sheet. Re-roll scraps to utilize all the mixture.
04 - Transfer the baking sheet to the freezer and chill the peanut butter hearts for 30 minutes until completely firm and set.
05 - Place chocolate chips and coconut oil in a microwave-safe bowl. Microwave in 30-second intervals, stirring between each interval, until chocolate is completely melted and smooth.
06 - Using a fork or dipping tool, carefully dip each chilled peanut butter heart into the melted chocolate. Allow excess chocolate to drip off, then return to the baking sheet.
07 - Immediately sprinkle flaky sea salt over each chocolate-coated heart before the chocolate begins to set.
08 - Refrigerate the chocolate-coated hearts for 10 to 15 minutes until the chocolate is completely firm and set.