Soak the wide rice noodles in a bowl of very hot water for 20 to 30 minutes until they are pliable but still firm to the touch.
In a small mixing bowl, whisk together the tamari, fish sauce, coconut sugar, and chili paste to create the stir-fry sauce.
Heat the avocado oil in a large wok or heavy-bottomed skillet over high heat until shimmering.
Season the sliced chicken breast with sea salt and black pepper, then add it to the pan, searing until golden and fully cooked through.
Add the sliced onion, bell pepper, and broccoli florets to the pan, stir-frying for 3 to 4 minutes until the vegetables are tender-crisp.
Stir in the minced garlic and cook for 30 seconds until highly aromatic, being careful not to burn it.
Drain the noodles and add them to the pan along with the prepared sauce, tossing vigorously over high heat until the noodles absorb the liquid and soften.
Remove the pan from the heat and fold in the fresh Thai basil leaves until just wilted, then serve immediately.