Heating the peanuts and spices not only toasts the nuts but also releases the fragrant aromas of the seasonings.
Because of the complexity of mole sauce, it should be kept on a low flame after it has come to a boil and stirred constantly. Otherwise, the sauce can burn and turn bitter.
Can't find prepared red mole sauce? Substitute 2 Tbsp. each mole paste and tomato paste mixed with 1/2 cup water for the mole sauce.