Best fixings for tiled dot and dab wall

[JamieB3009]

Hello,

I have a tiled bathroom where the porcelain tiles are stuck to plasterboard which is dot and dabbed onto breezeblock inner leaf of the wall. I need to fix a cabinet to the wall and want to know what the recommended plug/fixing would be for this type of wall? I cannot guarantee I can put all the fixings through the dabs so there may be a gap between the plasterboard and breeze block. Should the holes in the tile be drilled larger than the plug so it goes through the tile completely and doesn't load it at all?

Thanks

 

[Wayners]