Soak the brown rice noodles in a bowl of very hot water for about 10 minutes until they are pliable but still have a firm bite.
In a small jar, whisk together the tamarind paste, fish sauce, and coconut aminos until the mixture is smooth and well combined.
Heat the sesame oil in a large wok or skillet over medium-high heat, then add the minced garlic and sauté for 30 seconds until fragrant.
Add the shrimp to the pan and cook for 2-3 minutes until they turn pink and opaque, then push them to the outer edges of the wok.
Crack the egg into the center of the pan, scramble it quickly with a spatula until just set, and then toss it together with the shrimp.
Drain the noodles and add them to the wok along with the prepared sauce and red pepper flakes, tossing vigorously for 2 minutes to coat.
Stir in the bean sprouts and sliced scallions, cooking for just 1 minute more until the sprouts are slightly softened but still crisp.
Plate the noodles and garnish with crushed peanuts and a fresh lime wedge for a bright finish.