Lay your pretzels out on a wax paper or silicone-lined baking sheet, placing them in pairs so the curved sides face outward like wings. This step sets up the entire shape of your bat, so take a second to line them up neatly before moving on.
Add your mini chocolate chips to a microwave-safe bowl and heat them in short 20-second bursts, stirring in between each round. Stop as soon as the chocolate is smooth and glossy, since overheating it can cause the chocolate to seize up and turn grainy.
Dab about a teaspoon of melted chocolate onto the center where your two pretzels meet. Press them together gently so the chocolate spreads slightly and bonds the pair into one solid bat shape without cracking the pretzels.
While the chocolate is still soft, press one mini white chocolate chip onto each side of the center to form the bat's eyes. I like to place them close together for a slightly cartoonish, friendly look rather than something too creepy.
Transfer your tray to the refrigerator and let the bats chill for about 30 minutes, or until the chocolate has fully hardened. Once set, they're ready to serve or pack away for your Halloween spread.