Viúva de Lamego is not a "local" artist per se but they're a leading artisanal workshop in classic and contemporary Portuguese tiles. If you have the budget, their tailor-made tiles are something else, imagination is the limit. (source: my dad does a lot of house restorations in Portugal and some require custom tiles to fill in missing/damaged areas)

Can second this. Happy customer here. Amazing experience visiting their factory. Seems like a real institution. There were in fact a bunch of artist at the factory working with them there when we visited.