In The Garden: Identify my "fried egg" flower plant please

Hello. Can anyone help identify what my nephew refers to as the fried egg plant (owing to the flower shape/colour). Pictures attached.

It is an evergreen shrub, flowering in spring and has grown rather rapidly with multiple woody branches radiating from the one thick stem.

I don't particularly like the flowers, but it might help provide much needed ground cover in other parts of the garden if I can source some more. Perhaps there are other varieties.

Thanks in advance.

 

Chinese rockii tree peony,
http://www.treepeony.com/Tree-Peonies/White---Snow-Lotus-3-yr-old-Chinese-rockii-tree-peony.html

 

Gum Rockrose Cistus ladanifer.

 

It looks like Cistus ladanifer to me, too.

 

There are lots of others; for your situation check out C. x hybridus - this is probably the best one for general use.