Saw this on Facebook, so credit to them.
Install New cashback app, Green Jinn
( brand new, sainsbury's/ waitrose cashback only atm, also iPhone only atm)
Mozzarella is £1.50 at sainsbury's
Coupon for 20p- http://www.galbani.co.uk/wp-content/uploads/Galbani_Coupon_Revised_24.02.16.pdf
70p cashback from Green jinnhttp://www.greenjinn.com/#get-early-access
(Mods- there are no referral fees paid on this app, just including link to assist, but please remove if needs be)
70p cashback from Shopitize.
Bit convoluted, but didn't want people to miss out on free stuff. I don't actually buy mozzarella much, but can be handy to top up a pizza.