Heat 2 tablespoons of the oil in a large casserole or heavy pot over medium heat. Add the onion and cook for 3 to 4 minutes, until completely softened.Stir in the pine nuts and garlic and cook for 2 to 3 minutes, until the garlic becomes fragrant and changes color and the pine nuts are light brown and smell toasty. Raise the heat to medium- high, add another tablespoon of olive oil and the tomatoes, and cook, stirring occasionally, until the tomatoes soften and break down, 7 to 8 minutes. Add the ancho chiles, orange juice, broth, salt, and brown sugar and bring to a simmer.Simmer, stirring occasionally, until the chiles have rehydrated and plumped up and the sauce has thickened, about 8 minutes more.