Wash each kind of mushroom separately in cold water. Dry the mushrooms well on paper towels. Heat enough olive oil in a large sauté pan to coat the bottom, and heat it over medium-high heat. Add 1 piece garlic, 1 sprig of thyme, 1 sprig of rosemary, and the shiitakes. Sauté until all their liquid has evaporated and the pan is dry. Season them with salt and pepper. Transfer them to a bowl, let cool slightly, and then chop fine. Repeat with the other kinds of mushrooms, using a piece of garlic and a sprig of each herb each time.

Bring the chicken stock to a boil and season it well with salt and pepper. Keep the stock at a low simmer.

Place enough olive oil in a large sauté pan to coat the bottom, and heat it over medium-high heat. Add the onion and cook until it is translucent, about 4 minutes. Add the rice and stir until it is coated with the oil. Add the white wine and let it reduce until the pan is almost dry. When the wine has reduced, begin adding the hot chicken stock, about ¼ cup at a time, stirring constantly. Let each addition of stock be absorbed by the rice before you add the next. This will take 20 to 25 minutes in all. The rice should be very well cooked. Transfer the cooked risotto to a bowl and let it cool slightly. When it is warm rather than hot, mix in the mascarpone, egg yolk, and chopped mushrooms. Adjust the seasoning with salt and pepper.

Fill a medium saucepan with the canola oil. Clip a deep-frying thermometer to the side of the pan, and heat the oil to 350ºF.

Roll the risotto mixture with your hands into 20 equal balls, each about the size of a large melon ball. Place the egg whites and rice flakes in separate shallow containers. Dip the risotto balls, a few at a time, into the egg whites shaking off any excess) and then into the rice flakes, coating them thoroughly.

When all of the risotto balls are coated, fry them, a few at a time, until golden brown, about 4 minutes. Do not crowd the pan, and maintain the oil at a steady 350ºF. As they are done, remove the risotto balls from the oil and place them on a plate lined with paper towels to drain. Sprinkle with salt.

The risotto balls may be served immediately or kept at room temperature for 2 to 3 hours and then warmed in a 300º to 350ºF oven for 5 minutes. Just before serving, place a small drop of white truffle oil on each one. Arrange on a platter, and serve warm.

Chop the anchovies very fine, until they form a paste. Place the anchovies in a bowl and add the softened butter. Stir until completely combined; then season with salt and pepper.

Place a 12 x 12-inch piece of plastic wrap on a flat surface. Lay the tenderloin on the plastic wrap, with the slices overlapping slightly, so that the meat completely covers the plastic wrap. Place another piece of plastic wrap on top of the tenderloin, and pound lightly with a mallet or a rolling pin until the meat is about 1/8 inch thick. Remove the top piece of plastic wrap and season the tenderloin with salt and pepper.

Spread the anchovy butter over the tenderloin in an even layer. Then arrange the spinach leaves over the anchovy butter.

Pull up one end of the plastic wrap and gently roll the edge of the tenderloin over on itself, as you would a sushi roll. Make sure that the spinach and butter are tightly rolled inside the meat, and take care not to roll the plastic wrap inside the tenderloin. Once it is tightly rolled and covered with the plastic wrap, place the beef in the freezer for 30 minutes, or up to a week. (If freezing for more than 30 minutes, take the roll out 10 to 15 minutes before cutting.)

Remove the roll from the freezer, remove the plastic wrap, and cut the roll into ¼-inch-thick slices. Arrange on a platter, and serve cold.