I became a superyacht chef without any formal training. Here's how I turned my hobby into cooking for celebrities like Pharrell Williams while traveling the world.

• Rachel Cunningham has cooked on superyachts in Asia, in the Caribbean, and in the Mediterranean.
• The superyachts she works on feature submarines, spas, helipads, and even video-editing suites.
• She's cooked for the Formula 1 champion Niki Lauda, Pharrell Williams, politicians, and royalty.

This as-told-to essay is based on a conversation with Rachel Cunningham, a 38-year-old superyacht chef and the founder of thesuperyachtchef.com. It has been edited for length and clarity.

I was on holiday in Europe in September 2014 when I decided I wanted to enjoy the summer a little bit longer. One of my friends told me she'd heard of people who worked on yachts, and I immediately sent an email to the travel agency I was working at in Australia to tell them I was resigning. I loved working there, but I loved the thought of staying in Europe more.

I enjoyed cooking, so I decided to apply for a crew-chef position. In the winter months, the head chef leaves the yacht because the guests aren't there, but someone still needs to cook for the crew.

To apply for the job, I needed to first sit for a fire-and-water safety exam and have a medical exam to see that I was fit enough for the position. Because I was in Palma, in Mallorca, Spain, a hub for superyachts, I was able to get my certifications there.

I gave out my CV to a few people at a marina, and the captain of the yacht owned by the Formula 1 champion Niki Lauda offered me a temporary crew-chef job for that winter.

Since then, I've worked on 20 different superyachts in Asia, in the Caribbean, and in the Mediterranean. Here's what it's like.

I didn't have any chef's qualifications for my first two years

When I started, I wasn't worried about cooking spaghetti Bolognese for the crew, but I panicked when the captain said I'd need to cook for the owner because the Michelin-trained chef wouldn't be able to board the boat in time for his arrival.

I remember being so nervous, but they must've liked the sushi platter I made because I managed to get my next boat job thanks to their reference.

In 2016, I wanted to expand my skill set, so I took a ship's chef-certification course in France, which costs around $1,200. Leiths in London and Bluewater in Florida and Monaco also now offer this program.

I've taken temporary jobs in places such as Seychelles and Bali

I also worked on one superyacht for 2-and-½ years, where we would cross the Atlantic each season. I've cooked for stars including Pharrell Williams, politicians, and members of royalty.

The yachts I've worked on have personal submarines, helipads, and spas. They can have up to 12 hotel-style suites, so the owners will often bring multiple guests on board.

There was one yacht that had a full editing suite, which a National Geographic documentarian used to edit a video he'd made of the owners scuba diving.

I've now sailed into many glamorous marinas, but the one port that blew me away was in Malta. The galley of the boat had huge windows, so we could see big "Game of Thrones"-style castles on the hilltop as we arrived. It looked like a port you might have entered in the olden days.

My day usually starts at 6 a.m. when I fire up the ovens

I always prep fruit plates and pastries for breakfast, but I don't usually start receiving specific orders until the stewardesses tell me what the guests want to eat that day.

If any guests have any dietary issues, you must manage the galley so you don't cross contaminate. If you have guests with nut allergies, gluten allergies, or lactose intolerance on the same voyage, it can get quite hectic.

Even if the guests say they're going to eat onshore, I'm always prepared. Dinner reservations can fall through, or once they get to the restaurant, the yacht owners may decide the vibes are off and that they no longer want to eat there.

Sometimes, I'll get a call to make a midnight snack. If I have a group of younger people on the boat and they're going clubbing in Miami, I'll prep some wagyu-beef burgers for their return.

It's not uncommon that I get requests for dishes with luxurious ingredients, such as fresh Alaskan-crab legs

When I do, I'll arrange for them to be flown in from Alaska that day.

I'm in yacht-chef WhatsApp groups, where fellow chefs will try to come to your aid if you need assistance. If I'm in St. Barts in the Caribbean and I've run out of gluten-free flour, I can message other chefs in the area on WhatsApp to see who has any flour, and then I'll send the tender over to their boat to pick up the flour and bring it back.

But I don't just cook for the owners, the guests, and the crew — sometimes, I cook for the owner's pets. On one boat, I would need to sous vide — a method of low-temperature cooking — chicken breasts every day, which I would then finely dice for the owner's two dogs.

There have also been tough days

Working on a superyacht can be incredibly demanding. You'll only see the highlights of chef's days off on Instagram, and we never post about the tough days.

The biggest downside for me is being away from family and friends and missing birthdays or weddings. But I've also met some amazing crew on board yachts, including my new fiancé.

Once, we had to do an Atlantic crossing, and the boat took an absolute beating. There were a lot of things broken by the time we got to the other side, including a dining table.

When I do have some downtime, I'll go ashore and take a local cooking class

I'm always trying to learn. I've learned how to make pastries in Devon, UK, and I did a class in South Korea with the monk Jeong Kwan from "Chef's Table" on Netflix. I'm now planning to do a big sushi course in Japan next year.

I'll also seek out the perfect ingredients when I'm in a port. I've bought pata-negra hams in Spain and jerk spice from Antigua.

Chefs can earn between 6,000 and 12,000 euros a month

If you're working as a head chef on a busy charter yacht, you can earn between 6,000 and 12,000 euros a month.

Head chefs are paid for 12 months and only work six. Tips can vary from nothing to 50,000 euros at the high end. I have yet to receive a tip like this, but I know that those big tips do exist.

I get my jobs through word of mouth, but to help people who are starting out to connect with other yacht chefs, I launched thesuperyachtchef.com in 2019. As well as tips for chefs, it also has a jobs board.