here's a better photo of this area.

Can you post another photo to show what’s adjacent to the left of that area? And what is “under” the box?

Did you approve the idea to finish it like that? If not, the workers should remove the whole thing free of charge and make it a useful corner. It needs to be changed, no matter whose fault it is.
Here is an idea: move the light switches to edge of the wall on the right rear where they should have been, allowing for any planned trim. Remove the whole boxed area. Install a lower cabinet and a finished piece of counter material to fit the space. Then add a narrower 30" high upper cabinet (on top of the counter piece) to hold all your spices. You want it about 3" narrower so the light switches are okay on the wall. If a 36" high upper cabinet will fit below the vent, do that instead of a 30" tall cabinet.

To the left is a staircase going down to our entryway. It's 5 steps down and the door would be further to the left. Everything is covered in black plastic right now to keep the dust contained, so a photo from that angle won't really show much right now

@felizlady, that box has been there since the house was built in 1966. the foyer clost extends into it. We decided to move the HVAC return that was in the load bearing wall that we removed to this spot. No mistakes were made by the builder. There are lightswitches on the other side of the wall in the right as well.

I’m sorry; still trying to orient where things are. What is that, circled in red? An upper cabinet?

Here are two better views of the area. What you had circled is basically the ceiling of our foyer

Thanks. That’s so helpful! I’d probably have custom shelves built there, either L-shaped (just on the two walls) or a bookcase-style unit. If the area is part of the kitchen, I’d do it in a style and stain that compliments the cabinets. If that area is really separate, I’d paint it to match the walls.

Yeah I'd put shelves in

If this is right by an entry it is the perfect key drop spot. A pretty lamp with a mirror would be pretty. you could highlight it with an interesting paint colour as well, then it will look intentional.

Otherwise:Breakfast bar!