Formal:
* Очень вкусно (óchen' vkusno) - This is the most common and literal translation, meaning "very tasty."
* Превосходно (prevoskhodno) - This means "excellent" or "superb" and is a good option if you want to express a higher level of satisfaction.
Informal:
* Очень вкусно (óchen' vkusno) - This is still perfectly acceptable in informal settings.
* Вкуснятина (vkusnyatina) - This is a more informal and playful way to say "delicious" and can be used with friends and family.
* Ням-ням (nyam-nyam) - This is a very casual and childish expression of enjoyment, similar to "yum-yum."
* Просто объедение (prosto ob'yedénie) - This means "it's simply a feast" and implies that the food is incredibly delicious.
The best way to choose the right expression depends on the context and your relationship with the person you are speaking to.