Blanch the chiles in a large pot of boiling, well-salted water for 10 minutes. Cool under running water, discarding skin and seeds. Set aside.
Place the sausage in a food processor and chop. Transfer the chopped sausage to a large mixing bowl and stir in the raisins, rice and egg, set aside.
Place the tomatoes in a large (9x13”) baking dish: sprinkle with the garlic, chile powder, oil, salt, pepper and sugar. Roast for 25-30 minutes, until the tomatoes are softened and beginning to brown. Remove from the oven, stir and set aside. Reduce the oven temperature to 400º.
Stuff the sausage mixture into the blanched chiles. Arrange the stuffed chiles on their sides on top of the roasted tomato sauce. Gently spoon some of the sauce on top of the chiles. Cover the baking dish with foil and return to the oven for 20 minutes. Remove the foil and continue cooking for another 10 minutes.