Fill a saucepan with salted water and bring it to a gentle simmer over medium heat. Add raw shrimp to the water and cook for 2–3 minutes until they turn pink and opaque.

Immediately after cooking, transfer the shrimp to a bowl filled with ice water. Allow them to chill for about 3–5 minutes.

In a mixing bowl, combine Greek yogurt, lemon juice, Dijon mustard, chopped fresh dill, salt, and pepper.

Once the shrimp has cooled, drain and pat them dry. In the bowl with the dressing, add poached shrimp, diced avocado, chopped celery, and minced red onion.

Cover the bowl with plastic wrap and refrigerate the salad for at least 30 minutes before serving.