Place the brown rice noodles in a bowl of hot water and soak for 10-15 minutes until softened but still firm, then drain well.
In a small bowl, whisk together the tamarind paste, fish sauce, and coconut sugar until the sugar is fully dissolved.
Heat the 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 wok and cook 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, scramble it quickly until set, and then mix it in with the shrimp.
Add the drained noodles and the tamarind sauce mixture to the wok, tossing constantly for 2 minutes until the noodles are coated and tender.
Fold in the mung bean sprouts and sliced green onions, cooking for just 30 seconds to retain their fresh crunch.
Serve immediately topped with crushed roasted peanuts, red pepper flakes, and a generous squeeze of fresh lime juice.