Saute onions over high heat until dark brown bits form. Deglaze pan with some broth. Set aside.

Make a roux from the flour and oil. Gradually whisk in chicken broth until smooth. Whisk in spices and cocoa. Add remaining ingredients.

Reduce the heat to low and simmer for 15 minutes or until slightly reduced. Set aside until ready to use.

For more heat add chipotle chili powder to taste