How to Cook Asparagus Sous Vide

Ingredients

• 1 bunch asparagus, about 1 pound
• 1/2 teaspoon black pepper
• 2 tablespoons olive oil or unsalted butter
• Zest and juice of one lemon
• Sea salt for garnish

Directions

1. Fill a pot with water, then attach your immersion circulator. Set it to 180 degrees F and allow the bath to heat. While that happens, rinse the asparagus and trim the bottoms as you would flower stems, cutting away the tough, woody ends.
2. Place the asparagus in a zip-top, gallon-sized plastic freezer bag. Add the black pepper and olive oil, but hold off on the salt until the end, since salting now can make the asparagus look a bit grey. Move everything around in the bag so the spears are evenly coated.
3. Slip a few heavy soup spoons into the bag so it will stay down in the water. That little bit of weight helps the asparagus remain fully submerged, which means more even cooking.
4. Close the bag using the water-displacement method so you push out as much air as you can. Put the asparagus in the bag, lower it slowly into the water, and let the water pressure force the air up and out through the opening. When the air is gone, seal the bag just above the water line. You can do this while the water is heating, but be careful if the bath is already steaming.
5. When the water reaches temperature, lower the bag of asparagus into the pot. Check that the bag is fully under the water; if it bobs up, take it out and add a few more spoons for weight. For pencil-thin asparagus, start checking at 6 to 7 minutes. For average or thick spears, check at 8 to 10 minutes. If you are unsure, take the bag out at 8 minutes, open it carefully, and test a spear with a fork. If the fork catches instead of sliding in, seal the bag again and put it back in the water for another minute or 2.
6. Take the bag out of the water, switch off the circulator, and serve right away. Finish the asparagus with lemon juice and zest, plus some of the cooking oil or butter if you like, and a sprinkle of flaky sea salt, such as Maldon. Leftover asparagus will keep in the refrigerator for about 5 days.