1/2 cup coarsely chopped onion
1/4 cup sugar
2 tablespoons dry mustard
2 teaspoons salt
1 teaspoon coriander
1 cup lemon juice or vinegar
3 cups canola oil
1/4 cup minced jalapeño with some seeds
4 tablespoons chopped fresh cilantro

In food processor, blend first six ingredients for 1 minute. Continue to blend, and add oil in steady thin stream until emulsified. Turn off processor, and stir in jalapeño and cilantro with a spatula.