It's Acanthus spinosus, commonly known as 'Bears Breeches'. It can be invasive if it likes where it's planted. If you're digging it out make sure you have every piece of root out or it will regrow again. It can be a persistent nuisance, but personally I like them. You could dig it out and put it in a large pot!

The bees adore them so they are worth while keeping even though they are invasive.