Heat grill to high. Heat oil in a medium saucepan
on the grates of the grill
. Add the onion and cook until soft. Add the Port
and red wine and cook until thickened and reduced to 1/2 cup.
Transfer reduced wine mixture to a blender
and add the molasses, balsamic vinegar, thyme
and salt and pepper and blend until combined. With the motor running, slowly add the olive oil and walnut oil
and blend until emulsified.