For Marinade
Combine 1/2 cup soy sauce and 2 tbsp sesame oil in a ziplock bag.
Add chicken breasts to ziplock bag and marinade a minimum of 5 minutes, longer if desired.
For Chicken Lo Mein
Preheat oven to broil.
Begin boiling water and cook spaghetti noodles per package directions.
Place chicken breasts under broiler and cook for approximately 10 minutes. Flip and return to broiler for another approximately 10 minutes, until cooked through.
After the noodles are done cooking, drain and set aside.
In the same pan that you boiled the noodles, over medium heat, add 2 tbsp olive oil and saute garlic until fragrant.
Add remaining soy sauce, rice vinegar, remaining olive oil, and remaining sesame oil to the pan with the garlic.
Return noodles to the pan and stir until well coated with soy sauce mixture.
Cut chicken into bite size pieces, add to pan with noodles, and stir to coat.
Top chicken lo mein with green onion and sprinkle with sesame seeds.