Spread the miso and olive oil over the six filets and massage in well. Place the steaks in a freezer zip-top bag. Remove as much air as possible and refrigerate for 48 hours.
When ready to prepare the steaks, remove them from the refrigerator, wipe off the excess miso and allow them to come to room temperature.
For the rice tuile, put the rice and spring water in a pot over medium heat and cook until completely broken down. Remove from the heat and puree with an immersion blender. Thinly spread the purée onto acetate sheets or a Silpat to about 1/16-inch thickness. Dehydrate the rice until it is no longer tacky and curls at the edges. Break the rice sheets into irregular pieces and reserve indefinitely with a silica pack. When ready to serve, bring your frying oil up to 375 degrees. Fry the rice “irregulars,” quickly turning once. They should puff up quickly. Remove with a slotted spoon and set on paper towels. Season with sea salt and reserve.
For the pickled morels, heat a non-reactive sauté pan over medium-high heat. Film the pan with grapeseed oil, then add the shallots and fennel pollen. Stir the shallots for 30 seconds. Add the bay leaf, peppercorns, marjoram and tarragon to the pan and sauté for another 30 seconds. Add the mushrooms and increase the heat to high while stirring. Sauté the mushrooms until they are fully cooked through and most of the liquid has evaporated (6-8 minutes). Deglaze mushrooms with chardonnay and seasoned rice wine vinegar and reduce for 3 minutes. Add oil and honey, toss to coat and season to taste. Set aside at room temperature.
For the ash-roasted potatoes, prepare a wood fire. As the fire dies down, bury the potatoes in the hot wood ash and allow to cook through (about 15 minutes). Remove the potatoes from the ash with tongs. When cool enough to handle, brush the potatoes to clean off the ash. Toss with olive oil, fleur de sel and minced fresh herbs. Set aside.
Preheat oven to 400 degrees. Heat a large cast iron pan over high heat. Use grapeseed or canola oil to coat the bottom of the hot skillet. When the oil begins to shimmer, carefully add filets to the pan and cook for 2½-3 minutes on one side, turn and cook the other side. Place the skillet in the preheated oven and roast the filets until they reach 130 degrees (3-4 minutes). Remove the filets from the pan and rest for 5 minutes.
To serve, divide the pickled morels and potatoes evenly between six plates. Top with the filet mignon and garnish with two to three rice tuiles and a few slices of pickled ginger.