In 5-quart Dutch oven, heat oil over high heat. Add chicken; cook 5 to 7 minutes, stirring occasionally, until lightly browned. Using slotted spoon, remove chicken from Dutch oven. Reduce heat to medium; add onions. Cook 4 to 6 minutes, stirring occasionally, until softened. Add gingerroot, garlic and jalapeño chile. Cook and stir 1 minute. Add flour; cook and stir 1 minute. Add browned chicken, sweet potatoes, coconut milk, broth and remaining 1/2 teaspoon salt. Heat to boiling. Reduce heat to low; cover and simmer about 10 minutes or until sweet potato is tender. Gradually add spinach, stirring until wilted.