It really depends on what your nut is. How much do you need to take home in order to live comfortably, and how much do you need to pay someone to work in a responsible role as a manager of your business.
I would really suggest opening at least three stores, cause you probably can make one store operate really well and make about 60k a year, but what you will find is when you open your second store your food purveyor will take you more seriously, and when you open your third you will see about a 4% reduction in your food cost, and about a 4% reduction in your fixed costs, and the bulk expenses of insurance, and professional fees go down when you have multiple stores. And you will see might see the profits per store go down as you find yourself paying more labor to manage in your absence, but you will net about 150K a year, which is enough to hire a group supervisor if you really desire to disappear.
Also by owning multiple stores, its unlikely that all of them will have a down month, or year at the same time, so if one store is down, the other store will probably pick up the difference. Kinda like the old indian saying “its easier to break one arrow in half, but if you bind three arrows together it is very hard to break.”
I have set my stores, up so that each store has a manager with a good salary, and a performance based bonus. I work about 10 to 20 hours a week. Mostly administrative I usually visit the stores twice week for an hour each once during lunch rush, once during dinner rush. I plan to open up more, I would like to hire a supervisor once I hit 5 stores, so that I can take a couple of months at a time occasionally, and I will have someone at home doing rounds for me.