Based on the pronunciation along, I guess it is 青黄不接 （qing1 huang2 bu4 jie1）
青：green, which means the newly planted still growing wheat this year
黄：yellow, which means the old wheat gathered last year
不接：ends does not meet
青黄不接：the old wheat is almost gone but the new wheat is still growing: there is nothing to eat in the period in between. It generally means the old things are gone but new things are still not seen in the near future.
In your example, it might mean the old chefs are retiring but the new chefs are still not qualified enough. As a result, the food quality is decaying.