First, lay out all of the breakfast sandwich ingredients.
Next, preheat the olive oil in a nonstick skillet over medium heat.
Then, crack and fry the egg to your desired doneness.
To make the sandwich, begin by laying out the first toasted piece of brioche. Top it with the swiss cheese, followed by the fried egg, and finally a handful of fresh rainbow radish sprouts.
Finish the breakfast sandwich with the other piece of toasted brioche.
Finally, slice this scrumptious sandwich in half and enjoy!