Preheat oven to 350°F (175°C). Grease a 13x9 inch casserole dish.

Cook rotini pasta according to package directions.

During the last 5 minutes of pasta cooking, add broccoli florets to the boiling water.

Drain the pasta and broccoli thoroughly and return to the pot.

In a blender or food processor, combine cottage cheese, sour cream, and mayonnaise.

Blend until smooth and creamy.

Add the cottage cheese mixture to the drained pasta and broccoli.

Stir in the flaked salmon, cheddar cheese, milk, finely chopped onion, dry mustard, tarragon, and paprika.

Mix all ingredients well until combined. If needed, add additional milk to achieve desired moistness.

Season with salt and pepper to taste.

Pour the mixture into the prepared casserole dish.

Sprinkle a little extra cheddar cheese on top, if desired.

Bake in the preheated oven for 35-40 minutes, or until bubbly and heated through.