I feel your pain. Lee Valley Hardware had some really cool pantry inserts. I don't know if any would help your situation, but it's worth a check.

Reframe to larger doorway with either pocket or french doors, and then reconfigure shelving.

So it's shallow and wide. Weird.

- Can you open the wall a bit to enlarge the door?

- How about putting large Lazy Susans on the end that's difficult to reach?

If the door can’t be widened, can a door be put in the room behind the pantry, to access the inaccessible part?

If not, you could consider tall elfa carts with drawers and shelves, and put them on wheels. The only thing is, you’d have to roll the first one out to get to the one in the back, and it’s not optimal. I did this under my basement stairs, but only for things we don’t use much (in fact, I should probably get rid of that stuff, I don’t think I’ve seen it in 10 years.)

How do you plan to use the pantry? How is it outfitted right now?