Posting a photo would be helpful.

I had this problem and actually gave up.

The electricians could build out the wall so we could have lighting at the front of the medicine cabinet. It was going to look like they built out a wall rather than a feature. Nobody thought going with only overhead LEDs would feel right. I never did find a fixture I liked that would extend the six inches we needed: even looked at exterior lighting.

We weren't able to recess the medicine cabinet because it is an exterior wall.

Our traditional bathroom fixtures are in the garage waiting to be installed above the elegant mirror I purchased to go with the redesigned vanity that includes tons of storage. The LEDs and a semi flush fixture will provide layers of light. Drywall is going up today so pictures will have to wait.