Line a rimmed baking sheet with a silicone baking mat or parchment paper. Make sure it fits in your refrigerator before you start.
Set the 24 glazed donut holes within easy reach. Snap the 12 pretzel sticks in half to make 24 short stems and set them on a small plate. Pour the 1/2 cup of sprinkles into a small, shallow bowl.
Place the 10 ounces of dark chocolate melting wafers into a microwave-safe bowl or tall, narrow cup. If using chocolate chips instead, add the 1 teaspoon of coconut oil now.
Microwave on high for 30 seconds, then stir well. Continue heating in 30-second bursts, then 15-second bursts, stirring after each, until completely smooth with no lumps. Stop as soon as the last bits melt by stirring.
Lift your spoon and let the chocolate drip back into the bowl. It should fall in a smooth, flowing ribbon. If too thick, stir in the 1 teaspoon of coconut oil. Let sit for one minute so it is warm but not piping hot.
Hold one donut hole gently between your thumb and finger. Dip about the top third to half into the melted chocolate to form an acorn cap. Lift straight up and let excess chocolate drip back for a couple of seconds.
Immediately dip the chocolate-covered part into the bowl of sprinkles while the chocolate is still wet. Gently roll or press so the sprinkles cover the whole cap evenly. Lightly tap off any loose sprinkles.
Press the broken end of a pretzel stick half gently into the center of the chocolate cap about a quarter inch deep. Hold for a second or two so the chocolate grips the pretzel. Stand the finished acorn upright on the lined baking sheet.
Continue the dip, sprinkle, and stem process with the rest of the donut holes. If the chocolate starts to thicken, microwave it for 10 seconds and stir again. Leave a little space between the acorns.
Slide the baking sheet into the refrigerator for about 20 minutes, until the chocolate is completely firm. Alternatively, leave at room temperature for about 45 minutes. Touch one cap gently to check that it is dry and hard.
Arrange the acorn donut holes on a platter, cake stand, or wooden board. Serve them right away, or store them following the storage tips.