There are many ways to shoot at sunset. One is to frame something against the colors of the sun. Sometimes it is a discrete outline of something, like the outline of an animal or a windmill. Sometimes it is a solid shape like the jagged edges of this New Mexico mountain.
Sunset on mountains near Bosque del Apache National Wildlife Refuge, New Mexico. Canon 1Dx. 200mm. ISO 100. 20 sec. @F/16. EV +2/3.