In my kitchen the wall resembles the Himalaya
Range of mountains.

I would like to stick some plaster board onto the wall to cover it all up
and then put some tiles on. Length approx 19' (foot) x 18" high (inches).

The only bags of plaster that I can purchase from the local builders
supplies is quite large and most of it would be wasted. No DIY shops for 8
miles.

I was thinking of stick plasterboard to wall with something that I can put
in my sealant gun. I know this would probably cost more than plaster but at
least none would be wasted.

Your suggestions as to what to use would be most welcomed.

Kindest regards,

Jim