Dudleya brittonii, the Giant Chalk Dudleya from Baja California. Now don’t argue with me here – I have an answer for any objections you might have to my answer below.
Q: How do you differentiate between a dudleya and a echeveria?
They are very closely related! But Dudleyas are California native and summer dormant, while Echeverias are Mexican and winter dormant. Also Echeveria flowers are more brightly colored.