Crown molding type trim piece. Edit: Per Shelton Sound Design the proper trim piece is called "cove moulding" - not crown. :)

I would take the cabinets down, level the soffet, and move the cabinets up so they're against the bottom of it. I would then paint the white part red so it isn't so obvious.

I see the cabinets are recessed behind the soffit edge so crown molding can't be installed without bringing your cabinets out to the edge. A simple fix would be matching cove molding. You can get 3/8" or 1/2" cove and stain it yourself. It is always difficult to nail in such a close area unless you have a compressor and finish nail gun. Even then it has the tendency to split the wood. So I use "Grab-It" fast stick adhesive. It holds well. If you don't know what cove molding is, just go to Depot or Lowes and look for it. or ask an associate

Thank you Shelton. I knew it wasn't called "crown" molding but didn't remember the right word. I thought 'trim' would be too broad. I learn something everyday on this site.

I find u can make it attractive by filling the gap of the cabinet and ceiling by using glass of any color which goes and back of that led strip light

Given that the cabinet is set back from the soffit, I don't think a crown molding would work. I would paint the bottom of the soffit first and then glue in matching wood strips to fill the gap.

Shelton Sound design has a great idea with gluing the cove molding. I couldn't figure out a way to attach it with the full overlay doors and the tight space. I would also paint the underside of the soffit the same color as the walls. The white is just drawing attention to it.

Thanks for the comments so far! As people have mentioned, the cabinets are set back from the soffit, so the wood strip filler is a good idea, but how could we get a strip that goes from 1/4" on the left to 3/4" on the right without still having a 1/2" gap left on the right? And how to affix it? The cabinets are frameless, e.g. no face boards at all to nail to. Cove/crown moulding won't work for the same reason--it's only 1/4" gap at the ends.

How frustrating! Really, the only thing you can do is have the soffit redone to actually match the cabinets angles. Shoving in some rope lights into the crack would only call attention to it. Anything else would/could prevent them from opening and accentuate the misalignment, especially in the corner. I'd be tempted to call your real estate agent. Was this done after you agreed to buy?

If you have a gap that is a half inch difference from one end to the other, the soffet isn't square, level or whatever you call it, and you need to get that fixed so that you can rehang your cabinets, and they'll look right. It shouldn't be that much trouble for someone who knows anything about carpentry. That would also give you a chance to paint the underside so it blends with the rest of the paint. Anything else you do isn't going to solve the problem........

Without seeing the entire layout of the room, if it were my house, my 1st choice would be to have the soffits removed completely which would make your space seem less dated and probably make the room feel larger My 2nd choice would be to check to see if the bottom of the soffit or the cabinets are not level. Rehanging the cabinets so they are level is a fairly easy solution, but if the bottom of the soffits are not level,,,,, then I go back to my 1st choice. If you want to take the easy way out, then paint the entire room the same color including the undersides of the soffit and it should be less noticeable.

I would have this same problem had the builder not put a piece of cabinet trim up there. I have no doubt the alignment wasn't even. The piece of trim is about 1" . It is attached to the soffit just at the back edge of the cabinet. Not sure how attached but guessing glued as there is no evidence of nails or screws. What remains to be cleaned is just the width of the cabinet door, easily reached with a Swiffer. Attaching some pics but a little hard to see.

Hello folks - These are frameless cabinets - with no space to mount usual cove or crown above. This type of cabinetry is not intended to be mounted flush at the top - either to a ceiling or to a soffit such as yours.

In soffit applications, a slim moulding to match the cabinets - set back flush with or just barely forwared of the the box of the cabinets is recommended. Carefully done, this will fill your gap and minimize the irregularity of your soffit bottom.

Best wishes! Mark

I believe that is what mine is, what Someone's said, worded much better!

Bring in a good finish carpenter, and ask him/her the level of effort to make a cut 3 or 4 inches above the top of the cabinets, removing that lower strip of soffit material, then installing crown moulding at the top of the cabinetry, which would project inward to meet the cut edge of the soffit.