I'd wager an aquaponic or aeroponic system. Doing this significantly changes the crop you'd want.
For an aquaponic setup, fish could be farmed underneath the plants, and their nitrogen could be used for the plants.
Aeroponics though, make more sense here. The practice condenses extremely high amounts of food production in an indoor space, while minimizing resource use.
I have a very, very, similar setting to yours, for part of my book and the inhabitants use the three sisters method on the surface, and aeroponics in underground, artificially lit, caverns.
For the specific crops, you'd want tubers. They're more calorie efficient than most other things you could grow:
"According to the FAO, sweet potatoes top the list, yielding 70,000 calories per hectare per day, nearly twice as much as wheat—and far more than that if you use one of several fast-maturing varieties. Jeavons also recommends potatoes, leeks, and parsnips for those looking to maximize calories per acre."
But that also depends on whether they could be farmed using this method.
"The Advantages of Growing Aeroponically
Faster and more reliable growth: Plants produced aeroponically grow fast and relatively uniformly.
This can mean getting a jump start on spring planting, adding an additional lettuce crop during a season or being able to clone new plants from established stock quickly and with fewer losses.
Higher yields: Because plants have a smorgasbord of nutrients available to them almost continuously, they typically set and develop fruit quickly and produce more abundant yields.
Better flavor: Some growers and aeroponics enthusiasts report that aeroponically grown food crops have richer flavor profiles than plants grown almost any other way.
More flexibility: If you want to change the nutrient solution you’re using, it’s relatively easy to make a switch in an aeroponic system.
There’s less flushing and cleaning involved. Because plant roots aren’t installed in a growing medium, they are generally easier to inspect, manage and remove, if necessary.
It’s even possible to change from one type of system to another in process. Aeroponic systems are also easier to relocate than other types of indoor gardens. They’re lightweight, which makes them user friendly.
Space savings: By some accounts, growing a crop aeroponically uses as little as one-tenth of the space of growing that same crop in soil.
Practically speaking, there are definite space savings, but how much space will depend on a few factors.
You can produce plenty of clones and seedlings aeroponically, but growing a tomato plant to maturity will still take some room. It is easy to grow plants vertically using aeroponics, though, which can be a big space saver depending on your crop wish list and layout.
A-frame units are popular, especially for crops like herbs and salad greens.
Water savings: Some crops require a lot of water, and the prospect of saving nearly half on water consumption (40% or thereabouts) using aeroponics can be pretty compelling.
Cost savings: Because aeroponic systems use less water, less fertilizer and less space than other plant growing options, they incur lower operating costs over time."