1. For salad:
2. Pull noodles apart; place in large bowl. Pour enough boiling water over to cover generously. Soak noodles until tender, stirring occasionally, about 1 hour. Drain; return to same bowl. Cut noodles in half (or in thirds if very long).
3. Add snow peas, bean sprouts, cucumber, herbs, peanuts, and carrot to noodles and toss to blend.
4. Combine 1/3 cup water and all remaining ingredients in small bowl; whisk to blend. Season dressing to taste with salt and pepper. Stir dressing into noodle mixture.
5. Let stand 15 minutes, tossing occasionally.
6. ****
7. For scallops:
8. Sprinkle scallops with sugar, salt, and pepper.
9. Heat oil in large skillet over medium-high heat.
10. Add shallots, lemongrass, and garlic; stir 1 minute. Add scallops; sauté until just opaque in center, about 3 minutes.
11. Divide salad among 4 plates; top with scallops and serve.