1. Add the baby portabella mushrooms, onion, and garlic to a food processor and pulse until finely chopped.
2. Pat the steaks dry and season both sides with kosher salt and pepper.
3. Heat 1 tablespoon olive oil in a skillet over medium high heat and sear the steaks on both sides to your liking, then set aside to rest.
4. Add the chopped mushroom mixture to a pan with the remaining oil and cook until softened and browned.
5. Pour in the chicken broth and marinara, add the red pepper flakes, and simmer until thick, then stir in most of the parsley.
6. Thinly slice the pear and crumble the blue cheese over it.
7. Add the arugula, pears, and blue cheese to a bowl, scatter the walnuts on top, drizzle with dressing, and toss gently.
8. Slice the rested steak against the grain.
9. Plate the steak, spoon the mushroom marinara over the top, and finish with grated parmesan.
10. Serve with the pear arugula salad alongside.