Heat a little oil in a saute pan. Saute mushrooms over high heat until softened. Fold in the Truffles and Thyme. Set aside.
Make Risotto: Heat a little olive oil in a pot. Heat vegetable stock in a separate pot. Saute the shallot and garlic over medium high heat until translucent. Add the rice and stir until well coated with oil. Add more oil if needed. Add a cup of wine and cook down. Add another cup of wine. Cook that down until almost gone. Then ladle in the hot stock to cover the risotto in stages. Add liquid, cook it down until it is almost absorbed. Repeat this until the rice becomes soft, but maintains its shape. When it is almost fully cooked, stop adding liquid. Allow the risotto to absorb the liquid, stirring almost continuously. When it is dry, fold in the butter and Parmesan, plus half the mushroom mix. Season and taste. Spread the risotto onto a sheet pan in a thin layer. Allow to cool
Scoop the risotto into a ball the size you want your Arancini to be. We prefer cocktail size. But, you can do large ones to serve as an entree too. Flatten the rice down to about 1/4 inch thick disk. Place a chunk of cheese and some of the mushroom mix in the center of the disk. Then fold the rice around the piece of cheese and mushroom. make it into a ball. Be careful to seal the center well, so the cheese doesn't leak out when cooked. Repeat this process until all the rice is used up. Place the balls in the freezer. Allow them to set up at least an hour.
once the rice balls are well rested, and solid, heat some oil for frying in a pot of fryer to about 350 degrees. Set up a breading station: Put flour and bread crumbs in separate bowl. Whisk eggs in a third bowl. Start with flour, then go to egg, then breadcrumbs. Toss the rice balls in the flour. make sure there is an even coating, not to thick. Shake off excess. Transfer them to the egg, Allow the egg to evenly coat. Then transfer to the breadcrumbs. Make sure the breadcrumbs completely coat the rice. Any unsealed areas could develop leaks. For best results and easier cleanup, use one hand for flour and bread crumbs, and the other for the eggs. If you put a wet hand into flour or crumbs, it makes a mess. You can pre bread all the balls, or, drop them right from the crumbs in the oil.
Fry the Arancini in hot oil until they become golden brown. This should take about 5 minutes. Start with one to test the temperature of the oil. The cheese in the center should be melted, and the exterior should be a golden brown. If they get dark before achieving a molten center, turn down the temperature of the oil. Serve hot. A nice marinara or truffle aioli is a good accompaniment, or you can serve them as is.
