Place the brown rice noodles in a bowl of very hot water and soak for 8-10 minutes until tender but firm, then drain and set aside.
In a small jar, whisk together the tamari, fish sauce, lime juice, and honey to create the Pad Thai sauce.
Heat the avocado oil in a large skillet or wok over medium-high heat, then add the minced garlic and red pepper flakes, sautéing for 30 seconds until aromatic.
Add the shrimp to the skillet and cook for 2 minutes per side until pink and opaque, then push them to one side of the pan.
Crack the egg into the empty side of the pan and scramble quickly until just set.
Add the drained noodles and the prepared sauce to the pan, tossing everything together for 1-2 minutes until the noodles are well-coated and hot.
Fold in the mung bean sprouts and sliced green onions, cooking for just 30 seconds more to maintain their crunch before serving.