Line a large baking sheet (or two smaller ones) with parchment paper or a silicone baking mat to prevent sticking and make cleanup easy.

Spread about half of the mini pretzels in a single layer on the prepared baking sheet, leaving a little space between each pretzel for easier handling.

In a medium bowl, stir together the creamy peanut butter, powdered sugar, and vanilla extract until well combined. The mixture should be thick but still spoonable, like soft cookie dough. If it is too soft or oily, add another teaspoon or two of powdered sugar. If it is too stiff, add a tiny splash of milk or an extra teaspoon of peanut butter.

Using a small spoon or tiny cookie scoop (about 1/2 teaspoon), place a small mound of the peanut butter mixture onto the center of each pretzel on the tray. The mound should be about the size of a marble so it does not squeeze out excessively.

Gently press a second pretzel on top of each peanut butter mound to create a pretzel sandwich. Press just until the filling reaches the edges without completely squishing out. A little bit of filling escaping is fine.

Place the tray in the refrigerator for 10–15 minutes to help the peanut butter firm up. This makes dipping or drizzling with chocolate less messy.

Place the chocolate chips and coconut oil or vegetable shortening in a microwave-safe bowl. Microwave on 50% power for 30 seconds, then stir well. Continue microwaving in 15–20 second bursts at 50% power, stirring after each burst, until the chocolate is smooth and glossy. Alternatively, melt the chocolate and fat together in a heatproof bowl set over a pot of gently simmering water, stirring often and avoiding overheating.

Using a fork, dip each chilled pretzel sandwich fully into the melted chocolate, letting excess drip off through the tines, or dip just half of each sandwich for a partial coating. You can also leave them on the tray and drizzle chocolate over the tops with a spoon. Return each coated pretzel sandwich to the lined baking sheet.

While the chocolate is still wet, immediately sprinkle flaky sea salt, holiday sprinkles, crushed nuts, mini M&M’s, or other small candies over the tops as desired.

Chill the tray in the refrigerator for 20–30 minutes, or until the chocolate is firm to the touch. If your kitchen is cool, you can let them set at room temperature, but the fridge is faster and gives a cleaner snap.

Once the chocolate is set, transfer the peanut butter cup pretzels to a serving plate or an airtight container. Serve chilled or at room temperature, and store any leftovers according to the storage guidelines.