How to Make It
Place first 10 ingredients in a blender; process until smooth.
Heat a large saucepan over medium-high heat. Add oil to pan; swirl to coat. Add tomato mixture. Bring to a boil; cook, stirring occasionally, until reduced to 2 cups, about 10 minutes. Place cornstarch in a small bowl, and add 2 teaspoons water; stir until smooth. Add cornstarch mixture to pan; cook 1 minute or until mixture thickens, stirring constantly.
Cool completely. Cover and refrigerate up to 2 weeks.