1. **Mix Filling:** In a large bowl, use a hand mixer to beat the peanut butter and softened butter together until smooth and creamy (about 1 minute).

2. **Make Dough:** Add the vanilla extract and salt. Gradually beat in the powdered sugar, ½ cup at a time, until the mixture forms a firm, pliable dough. If it’s too sticky to handle, add a little more sugar; if it’s too crumbly, add a teaspoon of milk.

3. **Shape:** Line a baking sheet with parchment paper. Take about 2 tablespoons of dough and roll it into a ball, then flatten it slightly. Use your fingers to pinch the bottom and indent the top to form a heart shape. (Alternatively, roll the dough out to ½-inch thickness and use a heart-shaped cookie cutter).

4. **Freeze (Crucial Step):** Place the shaped hearts on the baking sheet and freeze for at least 30–45 minutes. The hearts must be very cold and firm before dipping, or they will fall apart in the warm chocolate.

5. **Melt Chocolate:** In a microwave-safe bowl, combine the chocolate chips and coconut oil. Microwave in 30-second intervals, stirring in between, until completely melted and smooth.

6. **Dip:** Remove 2-3 hearts from the freezer at a time (keep the rest frozen). Using a fork, dip each heart into the melted chocolate, tapping the fork on the edge of the bowl to shake off excess. Place back onto the parchment paper.

7. **Set:** Immediately add sprinkles if using. Let the hearts sit at room temperature or in the fridge until the chocolate shell hardens completely (about 15 minutes).