Do ahead: Peanuts can be prepared three days ahead and stored in an airtight container.

1. Pour oil in a large sauté pan and warm over moderate heat. Add peanuts in a single layer and cook, shaking pan occasionally, until nuts start to brown, about 3-4 minutes. Stir in lime juice, fish sauce and sriracha, and cook for 1 minute to evaporate some of the moisture. Remove pan from heat, add garlic, and toss well. Add sugar and stir to dissolve. Continue cooking, stirring occasionally, until most of the liquid has evaporated. Transfer peanuts to a rimmed baking sheet and allow them to cool.

2. Transfer nuts to a bowl and stir in cilantro, scallions, and salt. Stir to distribute ingredients evenly and serve.