Cook Spaghetti Squash: Preheat oven to 400 degrees F. Using long serrated knife, cut squash in half, hammering on the knife with a mallet (trust me, works like a charm). Scoop out seeds, place cut side down on a baking sheet lined with unbleached parchment paper or silicone mat, poke skin randomly with a fork and bake for 30-35 minutes. Remove from the oven and set aside.
Prepare Ingredients: While squash is baking, cut vegetables and meat. To make Healthy Chow Mein Sauce, whisk soy sauce, honey and fish sauce in a small bowl with a fork until well mixed (honey can be a pain sometimes). In a medium bowl, add chicken, cornstarch and half the sauce; mix.
Using a fork (sometimes hands afterwards), separate spaghetti squash into strands and place right on the baking tray.
Make Chow Mein: Preheat large wok on medium-high heat and add 2 tbsp of avocado oil. Add chicken mixture and cook until chicken is cooked, stirring occasionally. Add a splash of water if cornstarch starts to burn. Transfer to a medium bowl.
Return wok to the stove and add remaining 2 tbsp of avocado oil. Add garlic and cook for 30 seconds, stirring frequently. Add carrots, green onions, and cabbage; stir fry for 2 minutes, stirring frequently. Add spaghetti squash, remaining half of the sauce, cooked chicken, and sesame oil; stir gently until all ingredients are well combined. Serve hot, over brown rice, brown rice noodles or whole wheat spaghetti; or if you want a low carb meal, eat spaghetti squash chow mein on its own.