Preheat 2 cast iron pans. Coat the beef with oil then well in salt. Mix the peppercorns together and roll the beef in it. Coat well. When pans are screeching hot, place the beef in one and place the second pan on top, pressing down. This is called doing a "Pittsburgh". When the top and bottom get blackened, remove and let rest 3 minutes before slicing into 1/8-inch slices. Cut nori in half lengthwise. In a bowl, whisk together juice, soy and oil. Toss with spinach, reserve.
In a small bowl, mix together wasabi and creme fraiche. Using wet hands, lightly pat rice on bottom half of nori, 1/4-inch thick. Place 2 or 3 slices of beef on the rice. Place a small mound of salad diagonally across the rice from the top left corner to the bottom right. Drizzle with wasabi mixture on top of salad. Roll a cone by bringing the bottom left corner of the nori to half way up the right side edge then roll over. Moisten the top edge to glue. Repeat process.
Serve on small bed of salad or eat on the go.
MASTER SUSHI RICE
Wash rice at least 3 times or until water is clear. Fill rice cooker or casserole with water to about 1-inch over rice. I highly recommend a rice cooker more than 2 billion people use them in Asia for a reason. Slowly heat vinegar, mirin and sugar until very hot but not boiling. Fold in su (vinegar and sugar) with the hot rice, add enough so that the rice has a tart/sweet taste. Rice should be shiny, not mushy. Carefully clean bowl with damp cloth, cover and let rest for 30 minutes.
Drink Suggestion: Suishin, Japanese Sake Laurent Perrier Champagne