Combine plums, vinegar, honey and crushed red pepper in a medium saucepan. Bring to a simmer over high heat. Cover, reduce heat and simmer, stirring occasionally, until the plums start to break down, 5 to 10 minutes. Transfer to a blender or food processor and pulse several times into a coarse puree.Advertisement
Make Ahead Tip: Cover and refrigerate for up to 1 week.