I am not actually using functional programming in the kitchen :-)
I am re-writing my old cookingspace.com web app in Clojure with a new twist: the new web app will be an AI agent for planning recipes based on the food you have on-hand and based on a user's history, preferences, and the general mood they are in (food-wise). I have written some tools to convert my old relational database code for (more or less) static data (USDA nutrition information, recipes) to Clojure literal data.
Based on the type of food a user feels like cooking and what food they have on-hand, I need to transform recipes in an intelligent way to (hopefully!) also taste great after ingredients have substituted or morphed because a user would prefer a different type of sauce over a base recipe, etc., etc.
Anyway, working in Lisp and experimenting in a repl is making the entire process easier.
My wife and I are both very good cooks and we can make up super-tasty recipes on the fly with whatever ingredients we have on hand. I am betting on two things: I can automate our expertise and that people will enjoy using the system when it is finished.