Soak the brown rice noodles in a bowl of very hot water for 8-10 minutes until softened, then drain and set aside.
In a small jar, whisk together the tamari, rice vinegar, maple syrup, and the juice from the lime to create the pad thai sauce.
Heat the sesame oil in a large skillet or wok over medium-high heat, then add the minced garlic and shrimp.
Sauté the shrimp for 2-3 minutes until they turn pink and opaque, then push them to one side of the pan.
Crack the egg into the empty side of the pan and scramble it 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 bean sprouts and chopped green onions, allowing them to wilt slightly from the residual heat.
Plate the noodles and garnish with crushed peanuts and red pepper flakes for a spicy, textured finish.