Preheat the oven to 350 degrees F (175 degrees C).
Bring a large pot of lightly salted water to a boil. Cook elbow macaroni in the boiling water, stirring occasionally, until tender yet firm to the bite, about 8 minutes. Drain and place in an 8-inch casserole dish.
Combine tarragon, salt, white pepper, rosemary, chives, sage, and thyme in a small bowl. Mix well. Combine cottage cheese, Greek yogurt, and Gruyere cheese in another bowl; add the herb mixture and stir. Pour over the macaroni and stir to coat evenly.
Combine shallot, bread crumbs, and butter in another dish; sprinkle mixture over the macaroni.
Bake in the preheated oven until top is lightly golden brown, 25 to 30 minutes.