Veggie Potluck Pasta Salad

For dressing, in a small saucepan combine potatoes and 1 cup water. Bring to boiling; reduce heat. Simmer, uncovered, 8 minutes or until tender; drain, reserving cooking liquid. Rinse potatoes under cold water; drain well. In a small bowl pour hot potato cooking liquid over cashews. Let stand 15 minutes. In a blender combine soaked cashews and ½ cup of the soaking liquid; cover and blend until smooth. Add potatoes and the next six ingredients (through garlic powder). Cover and blend until smooth and creamy, adding water, 1 tablespoon at a time, as needed to reach desired consistency. Season with salt and black pepper. 2. Cook pasta according to package directions; drain. Rinse under cold water; drain well. Transfer to a large bowl. 3. Add the remaining ingredients. Add dressing; toss to combine. Garnish with additional fresh dill sprigs.