I never closed the loop here so here goes.
I built up a frame from spruce from the builders merchant. The idea was that it would fit a wine fridge we’d bought off ebay, have a couple of open shelves and a drawer for stuff.
For the most part I used loose tenons (dominos), cutting the mortices using a router and a homemade jig. For a second I considered hand cutting all of the mortice and tenons but after doing one or two I quickly bailed on the remaining hundred or so.
The router plus jig worked really well. Here are all the oak shelf slats complete with mortices. The hardest part was hand sawing and then shooting them all to the same length.
The drawer was a good excuse for some dovetails. I made the drawer front and sides out of oak. I believe the back was some leftover poplar I had and I did a ply drawer bottom. The front was painted so this could seem a bit wasteful, but I love that when you look inside you get a nice surprise.
And here it is in situ (before I got a drawer handle for it).
It has massively improved the utility of our kitchen giving us extra working surface and storage. 18 months on it’s holding up very well minus a couple of paint chips which I’ll sort at some point.