How to Make It
Combine hoisin, sugar, 1 tablespoon water, and fish sauce in a bowl, stirring with a whisk until sugar dissolves.
Heat a wok or large skillet over high heat. Add oil; swirl to coat. Add garlic and serrano chile; stir-fry 30 seconds or until fragrant. Add chicken; stir-fry 4 minutes. Add bell pepper and sliced onion; stir-fry 2 minutes. Add hoisin mixture; bring to a boil. Cook 30 seconds or until slightly thickened. Stir in basil and juice. Serve immediately.