Step 1

Blend dressing, tomatoes and onions in blender until smooth. Pour into stockpot. Bring to boil on medium-high heat. Stir in broth. Simmer on medium-low heat 15 min., stirring occasionally. Meanwhile, heat oil in large saucepan on medium heat. Add pasta; cook 1 min. or until golden brown, stirring constantly. Drain.

Step 2

Add pasta and water to tomato mixture in stockpot; cook on medium-high heat 10 min. or until pasta is tender and about 1/3 of the broth is absorbed. (The pasta should still be somewhat soupy.) Sprinkle with cheese.

Step 3

Top each serving with about 1 tsp. sour cream; swirl lightly with spoon.