The second thing is a vessel for the water. While you can use a large metal pot, it's not ideal – for one, you won't be able to see the food cooking. Also, water will evaporate off the surface, meaning you may need to top it up from time to time; this will affect your water temperature and the final cooking result. Fortunately, you can get around this issue by either covering the top of the pot with cling wrap or by covering the water surface with ping-pong balls. The better solution, however, is to purchase a clear-plastic food storage container that has a hole in the lid for the immersion circulator to fit through. These are inexpensive, and available online or in speciality stores.
The third item is a plastic bag to hold the food in as it cooks. Chefs use restaurant-grade bags and a vacuum sealer, but you don't need to go that route. Instead, use resealable freezer bags and the water-displacement method to remove the air from the bag prior to sealing it. (More information on this is available online.) Finally, you'll need a good iron skillet or an oven grill, so that you can sear the outside of your food right before it goes on the serving plate.
Admittedly, sous vide isn't the final word in cooking; you won't be replacing your microwave oven or hot-air fryer with one of these. Cooking times are very long, so you'll need to plan well in advance – even soft-boiled eggs take 45 minutes to cook. (They are delicious, though!) And some foods, like onions, don't turn out well with this technique. But if you have the time, and you love your protein to look and taste as if Heston Blumenthal or Jo?l Robuchon cooked it himself, then sous vide is the way to go.
Here's my recipe for beef brisket, which I adapted from different recipes. It results in something the British call "moreish" – everyone will want more. Every slice from edge to edge should be cooked to perfection.
