Creatio ex nihilo can be used in other contexts, as Nicholas does in his cooking metaphor. His remark fiat lunch is a pun on fiat lux.
An early draft of the manuscript also had Nicholas saying “And when it comes to charcuterie, saltpeter is my rock.” While it isn’t used so much these days, saltpeter or potassium nitrate has been used for curing meats. In this context it’s also a pun on Matthew 16:18 (“And I say also unto thee, That thou art Peter, and upon this rock I will build my church; and the gates of hell shall not prevail against it.”). The Greek name Peter (Πέτρος, Petros) comes from the word πέτρα, petra, which means “rock.” This wordplay would have been obvious to Matthew’s readers, as the New Testament was written in Koine Greek. It’s kind of like writing a story about a wealthy boy and naming him Richie Rich. In the end, I decided to cut this line because I thought the joke was weak, and the dialogue punchier without it.