Stir together yogurt, sugar, and vanilla in a large bowl.
Mix in peanut butter and stir until fully incorporated.
Cover mixture and refrigerate for at least 2 hours or until thoroughly chilled.
Add the yogurt-peanut butter mixture to your ice cream maker; follow the manufacturer's directions for churning.
About 5 minutes before the frozen yogurt is ready, pour in the chocolate chips.
Transfer frozen yogurt to an airtight container and freeze until solid.
To serve, scoop frozen yogurt into individual bowls or cones. Enjoy!
About ingredient substitutions ... someone asked me if this recipe would work with Greek yogurt. I told her to test it out and let me know, and the mixture ended up being too thick for her ice cream maker to mix. So stick with regular yogurt.