Dear Jeremy,
Thanks for your appreciation.
Moreover, we are sorry to say that there is no pre-built option for 15 minutes time slot. Also, it’s not an easy thing as it looks like that you are thinking. There has a critical calculation between the time slot with the opening, closing time, break times, ordering system, order management system, branch management system, etc. Hence, it’s not possible to consider a field to set your own timeslot duration.
However, if you need a customization service based on your specific needs and requirements then please send a message using our Envato Market (codecanyon) profile contact form to click here https://codecanyon.net/user/themelooks#contact (screenshot as reference https://prnt.sc/10o0iwt ) with your requirements with details to get a quote.
Best Regards,
ThemeLooks Support Team