Soak brown rice noodles in hot water according to package directions until al dente, then drain and set aside.
In a small bowl, whisk together the tamari, fish sauce, lime juice, maple syrup, and red pepper flakes to create the pad thai sauce.
Heat avocado oil in a large wok or skillet over medium-high heat and sauté the minced garlic for 30 seconds until fragrant.
Add the shrimp to the pan and cook for 2-3 minutes until pink and opaque, then push the shrimp to one side of the skillet.
Crack the egg into the empty side of the pan, scramble until just set, and then mix it into the shrimp.
Toss in the cooked noodles, bean sprouts, and the prepared sauce, stir-frying for 1-2 minutes until everything is well-coated and heated through.
Remove from the heat and stir in the sliced green onions, then serve immediately topped with fresh cilantro and crushed peanuts.