Bring a large pot of salted water to a boil for cooking pasta.
Meanwhile, puree cottage cheese until smooth in a blender or mini food processor. Add buttermilk and oil; process until smooth. Scrape into a storage container and stir in dill, parsley, Parmesan, lemon zest and lemon juice. Season with salt and pepper. Cover and set aside in the refrigerator.
Cook pasta in boiling water until just tender, about 10 minutes. Add peas and cook until crisp-tender, about 1 minute. Drain and rinse under cold running water.
Place pasta and peas in a large storage container and toss with tomatoes and scallions. Season with salt and pepper.
Just before serving, toss salad with dressing.
Per serving :
4 g Fat;
1 g Sat;
2 g Mono;
3 mg Cholesterol;
35 g Carbohydrates;
11 g Protein;
5 g Fiber;
182 mg Sodium;
217 mg Potassium