Hammer & bolster chisel with help from a scraper with a chisel edge (as opposed to a square edge). It depends how well the tiles are stuck down but the chip worktop is unlikely to survive, especially if it was professionally made using quality tile adhesive; unfortunately removing the tiles will almost certainly destroy the chip. Post formed worktops are high density chip but the standard stuff is total crap & maybe you should budget to replace the lot; tiles wouldn’t be my choice for a replacement worktop either!
Appreciate and understand everything you've said and it is standard crap chipboard, two layers of 18mm glued and screwed together.
My idea was to use a very sharp bolster or sharpened paint scrapper to cut betwwen the tile and adhesive. And then come up with some method of removing/smoothing the remaining adhesive, I was thinking a very coarse belt sander.
Why are you not keen on tiled worktops? is there any other covering that could be used?