Socket in island

I need to fit a socket in an island where there is no void as such.

So socket will have be let into a fixed panel of one the units (18mm thick) and cable run inside unit in trunking.

What is the best option for a back box which will look neat and not have any holes - I'm currently considering having a square hole cut in the panel and then fixing the faceplate by socket screws going though panel and into a pattress behind the panel and then trunking out of the pattress. (although usual pattress fixing holes will be present)

Any better ideas?

Thanks!

metal back box usually works fine, there's gaps around draws etc for running cables

How about a pop up socket on the worktop, that drops down in the back of one of the cupboards?

something similar to this? 

Thanks everyone. Unfortunately client does not want anything in worktop...

Rear of back box will be visible inside cabinet so metal back box not really an option.

Hum

No metal back box visible inside the cupboard. What about a dryline  box?

Or say no it's not possible.

Standard metal backbox fitted into the panel, stripwood around the internal projection, the back covered with thin ply or similar, all finished  to match the cabinet interior.   

? https://www.electricalcounter.co.uk/products/Switches+%26+Sockets/G%26H+Brassware/Accessories/Back+Boxes/Brushed+Steel+Double+Surface+Socket+Back+Box+Pattress+2+Gang+32mm/2949588339

I've decided to go with a hybrid solution:

SSO into single 25mm metal back box within fixed panel - 7mm protruding inside unit.

Cut single-metal-back-box-sized square out of double PVC pattress.

Within unit fit pattress over protruding bit of metal back box.

Trunk cable out of pattress - fit blank to pattress.

Repeat to provide 2 x SSO.

Thanks for all input!