While we can get many things from Iceland in Fuengirola (450km round trip) and really good fish and chips at the Crispy Cod on the seafront, there are some things which are not available or there are no substitutes in Spanish shops such as:
Decent smoked haddock (not the grotty frozen offcuts sold by Iceland) preferably undyed. Or smoked cod.
Proper Turkish Delight (i.e. not gelatin posing as TD)
Smoked gammon ham
Pork leg ts with skin on (for crackling!)
Some of these can be bought from "British Corner Shop" but, with Brexit, who knows for how long.