Start by preparing the vegetables. Cut off the top and bottom of the red onion and peel off the exterior skin. Slice the onion in half and then in equal vertical cuts.
Slice the green bell pepper into thin slices. The easiest way to do this is to cut the pepper from the bottom (upside down); the seeds will stay mostly within the stem.
Heat a large skillet (cast-iron works great if you have one) to medium heat. Add the oil and allow it to come to a sizzle. Add the sliced green peppers and onion.
Sprinkle the seasonings on the vegetables. Sauté for 8-10 minutes, or until the vegetables have softened and caramelized. Add more salt and pepper to taste if desired. Enjoy!