Question: I'm writing a letter and I've already used the word "delicious" in my writing, I'm just looking for a phrase or idiom that completes my sentence, in my mother tongue we have a phrase that says : "your food was as much delicious as its taste is still under my tongue" do we have an English phrase or idiom that I can use in the given concept?

Answer: 
From what comes to mind, I'd suggest [*finger-licking good*](https://idioms.thefreedictionary.com/finger-licking+good) and [*lip-smacking*.](https://www.merriam-webster.com/dictionary/lip-smacking)
There are a few synonyms that could be used instead of delicious such as [sublime](https://dictionary.cambridge.org/dictionary/english/sublime) or [divine](https://dictionary.cambridge.org/dictionary/english/divine).