Combine the cucumber, scallions, and red bell pepper in a medium bowl and refrigerate.
In a medium non-stick saute pan, lightly cook carrots and mushrooms in a medium pan with the sesame seeds, adding 1 tablespoon of water at a time. Continue to cook until carrots and mushrooms are tender. Cool. Add to cucumber mixture and keep refrigerated.
Combine all ingredients for dressing and mix well. Toss with vegetables and noodles.