What is can you cook what the rock is cooking?

"Can You Smell What The Rock Is Cooking?" is a catchphrase popularized by Dwayne "The Rock" Johnson, who is a famous professional wrestler, actor, and TV personality. The phrase was first made popular during his wrestling career in the 1990s and early 2000s.

As for the question itself, "Can you cook what The Rock is cooking?" it is simply a way of asking if someone is capable of doing what The Rock is doing - which is usually being tough, confident, and successful in his endeavors. It's not a reference to any specific meal or recipe.