Cook the noodles according to package directions. Drain.
Combine ⅓ cup tamari/soy sauce, sweet Thai chili sauce, rice vinegar, sesame oil, ginger, and chili flakes. Mix in ¼ cup water.
In a large skillet, toss the chicken with the flour. Add 2 tablespoons butter and set the skillet over medium heat. Cook until crispy, about 5 minutes. Add 1 tablespoon butter, 1 tablespoon tamari/soy sauce, and the garlic. Cook another minute, then remove the chicken from the skillet.
To the same skillet, add the shallot, bell peppers, and green onions. Cook for 5 minutes, then add the sauce, the noodles, and the chicken. Toss to combine, cooking another 3-5 minutes until the sauce coats the noodles. Mix in half the basil and remove from the heat.
Serve the noodles warm, topped with the additional basil + sesame seeds.
