Mix together the soy sauce, rice vinegar, ground ginger and tomato paste in a small bowl. Add the ginger ale and xanthan gum, and whisk to ensure there are no clumps. Set aside.

Heat the oil in a large skillet and add the chicken. Cook for 4-5 minutes, turning frequently.

Add the peppers, continue cooking for a few minutes, then add the sauce. Cook until the sauce thickens.

Transfer to a serving plate and garnish with green onions and sesame seeds.