No, mole sauce does not always contain chocolate. Mole sauce typically contains a combination of spices, herbs, and chili peppers such as ancho chilis and pasilla chilis.  It can also include a variety of nuts or seeds like sesame, almonds, or even pumpkin seeds.  Chocolate is sometimes added to mole sauces, but it is not always included. The addition of chocolate helps to add depth and complexity to the flavor profile of the mole sauce.  Other popular ingredients used in mole sauces include onions, garlic, tomatoes, tomatillos, cinnamon, and cloves.