How to Make It
Bring 2 quarts water, turmeric, and vinegar to a gentle simmer in a medium saucepan over medium. Adjust heat as necessary to maintain a gentle simmer.
Using a whisk, swirl water in a circular motion until a whirlpool forms. Gently crack egg into center of whirlpool. Cook until white is set, about 3 minutes. Using a slotted spoon, remove egg from pan; place on a plate lined with paper towels.
Toss arugula with olive oil in a medium bowl. Arrange lentils, quinoa, and avocado in bowl. Sprinkle salt and pepper over top. Place egg in center of bowl.