Start your grill, broiler, or over an open flame on the stove top, char the outside of the peppers completely. Allow to cool and scrape off the outer skin off. Make a small incision down one side and open partially. Remove any membrane threads and seeds. Set aside.
Meat and Fruit Filling
Add the vegetable oil to a medium sauté pan over medium heat. Add half of the diced onions and cook until translucent, about 5 minutes. Add the chicken, cumin, kosher salt and pepper and cook for about 5 minutes more.
Add the diced apples, apricots, cranberries, pears, garlic, pumpkin seeds and cook for 3 minutes. Stir in the tomato paste and cook for 3 more minutes. Add the white wine and simmer until the chicken is tender and sauce has thickened, about 5 minutes. Season with sugar, salt and pepper to taste, and then remove from the heat. Set aside to cool slightly.
Stuff each poblano pepper with a quarter of the chicken mixture and set aside. Gently wrap the sides together so pepper encases filling.
Nogada Sauce
In a medium skillet over medium heat, cook the other half of the diced onion in the oil until translucent, about 5 minutes. Add the minced garlic and cook for 3 minutes. Add the wine and simmer until it is almost completely evaporated, about 10 minutes. Add the heavy cream and simmer until reduced by half, about 10-15 minutes more, stirring occasionally. Stir in the chopped walnuts and season to taste with salt and freshly cracked black pepper.
Pour the walnut cream sauce on top of each stuffed poblano pepper and sprinkle with the cilantro and pomegranate arils.