Cookies? No, they are Senbei!!
You don't need a griller. Just tap senbei, and you'll be able to grill more and more senbei.
Senbei are Japanese rice crackers (really good with green tea). They have variety of flavors, but one of the most popular ones is this, Nori. It's a soy sauce flavored senbei with dried seaweed.
You are not alone. If you give some senbei, you can get help from some people and things(?) to grill senbei faster.
Grill more senbei and unlock achievements!! They will show the value of senbei that you have grilled.
Will it be as valuable as a car, house.....or even something bigger?