Line a baking sheet with parchment or wax paper.
Add the chocolate chips and vegetable oil to a microwave-safe bowl. Microwave the chocolate chips at 50% power for 30-second increments, stirring between each increment, until the chocolate is smooth.
Carefully dip all or a portion of the pretzels into the chocolate, shaking off any excess, then arrange them on the lined baking sheet. If decorating with sprinkles, apply them right away.
Let the pretzels sit at room temperature until the chocolate is fully set, about 30 minutes to 1 hour, or speed things up by placing the baking sheet in the freezer for 8–10 minutes. Once set, transfer the chocolate-covered pretzels to an airtight container, layering them between sheets of wax or parchment paper to prevent sticking. Store at a cool room temperature for up to 2 weeks.