Bring 4 quarts of water to a rolling boil in a large pot. Add a pinch of kosher salt and a splash of olive oil.

Carefully add the gluten-free macaroni noodles to boiling water. Cook according to package instructions until al dente, about 6–8 minutes.

Once drained, rinse the cooked noodles under cold running water for 1-2 minutes. Drain well again.

In a large mixing bowl, combine cooled noodles, chopped celery, cubed rotisserie chicken, and minced sweet onion. Add mayonnaise, lemon juice, salt, pepper, and garlic powder. Toss gently until evenly coated.

Cover with plastic wrap and refrigerate your creamy gluten-free macaroni salad for at least 30 minutes before serving.