Bring to a boil and cook on medium-high until it has reduced to about 1/2 cup. ~10-15 minutes (watch so it doesn’t burn)
Add in the rest of the ingredients, stir, reducing the heat to medium and bring to a boil.
Reduce to a simmer and cook until thick and dark. ~8-10 minutes.
Remove from the heat and using an immersion blender, blend until no pieces remain. If you don’t have an immersion blender, pour in a blender venting the lid.