Soak tamarind paste in boiling water for 10 minutes.

Strain tamarind mixture to remove seeds and fibers.

Combine tamarind liquid with fish sauce, rice vinegar, sugar, cayenne, and 2 tablespoons of oil.

Soak rice noodles in hot water for 20 minutes until softened but not fully tender.

Drain noodles.

Beat eggs with salt.

Heat 1 tablespoon of oil in a skillet over high heat.

Add shrimp and salt, cook until opaque and browned, about 3 minutes.

Transfer shrimp to a plate.

Add the remaining oil to the skillet.

Add garlic and shallot, cook until golden brown, about 1 1/2 minutes.

Add eggs and stir until scrambled and barely moist, about 20 seconds.

Add noodles, dried shrimp, and salted radish (if using) to eggs.

Toss to combine.

Pour fish sauce mixture over noodles.

Increase heat to high and cook, tossing constantly, until noodles are evenly coated.

Scatter peanuts, bean sprouts, all but 1/4 cup scallions, and cooked shrimp over noodles.

Continue to cook, tossing constantly, until noodles are tender, about 2 1/2 minutes. If not yet tender add 2 tablespoons water to skillet and continue to cook until tender.

Transfer noodles to a serving platter.

Sprinkle with remaining scallions, peanuts, and cilantro.

Serve immediately with lime wedges.