Steps
1. Season the filet mignon with salt and pepper on both sides.
2. Heat 1 tablespoon of olive oil in a skillet over medium-high heat.
3. Add the filet mignon to the skillet and cook for about 4-5 minutes on each side for medium-rare, or until desired doneness. Remove from the skillet and let it rest.
4. In the same skillet, add the remaining olive oil and sauté the onions until translucent.
5. Add the garlic and mushrooms, cooking until the mushrooms are browned and soft.
6. Pour in the heavy cream, stirring to combine, and let it simmer for a few minutes until slightly thickened.
7. Taste and adjust seasoning with salt and pepper.
8. Serve the filet mignon topped with the creamy mushroom sauce and garnish with fresh parsley.