Heat stock to boiling over high heat. Add and cook noodles until tender but firm to bite, about 12 minutes, drain and set aside.
In small bowl, mix together sour cream and yogurt until smooth. Set aside. Melt margarine in large skillet over medium heat. Add and saute garlic 1 minute. Reduce heat to low and add yogurt mixtures, blending well, add noodles and toss gently until sauce is evenly distributed. Sprinkle with parmesan cheese.
Makes 8 (1/2 cup servings).