How to Make It
In a small bowl, whisk lime juice, fish sauce, sugar and 2 Tbsp. water.
In a 12-inch nonstick skillet, heat 1 Tbsp. oil over medium-high heat until very hot; swirl to coat skillet. Add shrimp and stir-fry until just pink, about 3 minutes. Transfer to a medium bowl.
Add 2 tsp. oil and half of eggplant to skillet. Cook, undisturbed, for 2 minutes, then stir-fry for 30 seconds. Transfer to bowl with shrimp. Add another 2 tsp. oil; repeat with remaining eggplant. Make a well in center and add remaining 1 tsp. oil, garlic, chilies and scallion. Stir-fry until fragrant, about 1 minute.
Add shrimp, eggplant and sauce to skillet. Cook, tossing well, until heated through, 30 seconds to 1 minute. Stir in basil. Serve with lime wedges and rice noodles, if desired.