I live just a couple of minutes from here. You have to understand that in Abu Dhabi there are housing communities here and there throughout Abu Dhabi. These communities usually have a shopping center which usually have a supermarket and various other stores where the community residents (or even nearby ones) can shop, eat out or meet up with friends. Thus, The Garden Plaza is such a community. It has a supermarket, and Jones the Grocers is located besides it.
Personally, I found it to be rather a gourmet type store where one would go to buy specific ingredients wrapped up in special packaging. Indeed, chefs sometimes put on culinary demonstrations there. The restaurant there provides a gathering place for friends in the neighborhood or if you are staying in hotels close by , it is an option to dine. I have heard it is pretty expensive to dine there, I have seen the place but haven't actually gone in to dine.
To get here, get on the 16th Street ( a main root road there) go right past the shops on this road and at the end of the road you will see GEMS school, turn right from here onto Street 3. Continue down the road until you reach street 20, turn at the roundabout onto this road on the opposite side, go straight , turn left ( you have too -no road ahead after this) so you won't get lost. There is police station after the mentioned roundabout, so make sure you turn at the roundabout before the police station. As you turn left and continue driving for a few seconds you will see the Garden Plaza and then the shopping complex. There are many other options nearby here to dine such as Mugg and Beans at Etihad Plaza-they have a sitting area outside, also in Abela's Shopping Store. there is the Lavanda restaurant, another place to dine for breakfast, lunch or supper. I like to buy their grilled chicken!
Then if you don't want to dine , you have the option to buy hot food at the deli in Abelas. They have all kind of hot pies such as roast chicken pie, Steak and Kidney pie, Cornish Pasties and so very much more. Lots of sandwiches, salads, sweets etc..