Thoroughly rinse the truffle under a cold stream of water to remove excess dirt, then brush it with a semi-hard brush to eliminate any traces of impurities and carefully dry it before placing it on a cutting board.
Slice the truffle into very thin shavings using a truffle slicer and set them aside. In a skillet, heat the oil along with the butter and melt the butter over low heat. Peel the garlic clove (removing the inner sprout) and let it turn golden in the skillet with the oil and melted butter for a few minutes. Then remove it with a fork, turn off the heat, and add the previously sliced truffle shavings. Heat by gently mixing the truffle shavings, while at the same time, cook Nonna Rina's Girasoli in plenty of salted water for 3-4 minutes. Place the Girasoli in the truffle-infused seasoning, then mix carefully adding some pasta cooking water if necessary to bind. Serve the dish with a few shavings of black truffle.