Heat the olive oil in a saute pan over medium heat. Add the onions and sugar, and cook on medium until they start to talk to you. Lower the heat to low and cook slowly, stirring occasionally, for about 45 minutes or until the onions are very soft and caramelized.
Turn up the heat on the onions to medium-high. When they start to sizzle a bit, add the wine, and cook ~3 minutes, stirring, to deglaze the pan and boil off most of the liquid. Remove from the heat and set aside. Season with a pinch of kosher salt.
Process the soaked cashews in a food processor until smooth. Add half of the caramelized onions to the food processor. Add the remaining ingredients and process until smooth. Transfer to serving dish.
Roughly chop the reserved caramelized onion and top the dip. Garnish with fresh green herb. Serve with toasted crostini or cracker of choice. Yields: 12 servings.