Boil the noodles until al dente. Drain the noodles reserving a cup of pasta water and rinse them in cold water. Drain the noodles again and transfer them to a bowl. Add 1 tablespoon of sesame oil and toss to coat. Refrigerate the noodles for at least an hour until ready to serve.
Season the shrimp with salt and pepper and grill for 3-5 minutes on medium heat or until pink, turning once.
In a saucepan, slowly simmer the soy sauce, vinegar, sugar, peanut butter, 1 tablespoon of the sesame oil, the red chili paste, ginger, garlic, and pasta water (adding more if needed to thin the sauce.) If you like it saucy, double this part of the recipe.
Saute the sugar snap peas and sweet red pepper in a ½ tablespoon of the sesame oil until the vegetables are soft and crunchy. When ready to serve, add the noodles, the sauce, and the vegetables in a bowl and mix well to coat. Add in the mandarin oranges, roasted peanuts, sesame seeds and grilled shrimp.