Spicy Mongolian Beef is a variation of the classic dish that adds a kick of heat to the recipe. In this version, red pepper flakes or chili paste are added to the sauce to give it a spicy and fiery flavor. The beef is still cooked in the same manner, but the addition of the spicy sauce takes the dish to a whole new level. This recipe is perfect for those who enjoy a little heat in their meals and want to add some excitement to their dinner table.