How to Make It
In a small saucepan, combine the vinegar and sugar and bring to a boil. Add the garlic and ginger and simmer over moderate heat until the mixture has reduced by one-third, about 10 minutes. Remove the pan from the heat, add the tarragon and thyme and let steep for 5 minutes.
Meanwhile, in a large saucepan, heat the oil until shimmering. Add the onion and both peppers, season with salt and cook, stirring occasionally, until the peppers begin to soften, about 5 minutes. Add the corn and scallions, season with cayenne and cook, stirring, until the corn turns bright yellow, about 2 minutes.
Add the vinegar mixture to the corn and bring to a simmer. Cook over moderately low heat just until the corn is tender, about 5 minutes. Discard the thyme and tarragon. Season the relish with salt and let cool. Refrigerate for at least 24 hours before serving.
Grilled chicken, pork or shrimp.