Preheat oven to 425 and prepare a sheet pan lined with parchment paper. Bring filets to room temperature.
Using a damp paper towel, gently wipe the wild mushrooms, cutting off any tough stems and halve or slice into large clusters. Drizzle mushrooms with half the avocado oil, salt, pepper and herbs de provence. Roast on the middle rack for 10-12 minutes, turning over midway through, until lightly browned.
While mushrooms are roasting, prepare gremolata. Add all ingredients in a small bowl and stir well to combine. Set aside.
Next, prepare steaks. Pat steaks until very dry and season liberally on all sides with mineral salt and freshly ground black pepper.
Heat a small saute pan or cast iron over medium high heat for 2-3 minutes. Add remaining avocado oil, then steaks, leaving undisturbed to sear for 2-3 minutes on the first side. Flip, and continue to sear on all sides until golden brown. If serving rare, steaks will be ready to rest. For medium rare+, add pan with steaks to the hot oven for an additional 2-3 minutes then set aside to rest.
While steaks are resting, assemble serving plates with wild mushrooms. Add filets and drizzle with gremolata. Serve and enjoy!