Puffed rice does not need to be cooked
They're similar in texture to rice crispies but you need to get plain puffed rice,nothing with any added sugar or preservatives etc.
Whimzees can be purchased from Viovet either as Whimzees or Antos(Antos are very similar,but still better than Greenies).
https://www.viovet.co.uk/Whimzees_Cr...g_Chew/c19229/
That's just one,you can get different shapes though.
The rice pop treats they make for hamsters and other small pets are junk
They're loaded with dyes and sugar,and are just a waste of money.