Place the brown rice noodles in a large bowl and cover with very hot water, soaking for 8-10 minutes until tender but firm, then drain.
In a small bowl, whisk together the tamari, lime juice, and maple syrup to create the Pad Thai sauce base.
Heat the toasted sesame oil in a large skillet or wok over medium-high heat.
Add the minced garlic and shrimp to the skillet, sautéing for 2-3 minutes until the shrimp are pink and opaque.
Push the shrimp to one side of the pan and crack the egg into the empty space, scrambling it quickly until just set.
Add the drained noodles and the prepared sauce to the skillet, tossing everything together for 1-2 minutes until the noodles are well coated and heated through.
Fold in the mung bean sprouts and sliced green onions, cooking for just 30 seconds to maintain their crunch.
Remove from heat and garnish with crushed peanuts and red pepper flakes before serving.