Mix the flours together on a wooden pastry board. Add the oil and salt. Pour the water in a little at a time, working the flour with your fingertips. When the texture becomes crumbly, begin to knead with your hands. The more you knead, the more glutens will form, which will strengthen the pasta sheets. The movement is all in the wrist: roll the pasta outwards in front of you, then fold it over onto itself and repeat the rolling movement. When the ball of dough is smooth, silky and no longer sticky, wrap it in plastic wrap and let rest for 30 minutes at room temperature.

Roll the dough out to a very thin, wide, uniform sheet of pastry. Dust with semolina and let dry on the board for about 20 minutes, until the dough is no longer sticky. Cut into rough squares and diamond shapes with a pizza cutter or sharp knife. The pasta can be used immediately or dried thoroughly and stored in a paper sack for months.

Cook the pasta in boiling salted water until al dente. Drain the pasta, reserving some of the water. Prepare the sauce.

Process the walnuts with a clove of garlic, the cream, a pinch of salt and a ladle of the pasta cooking water. Dress the pasta with the sauce and add a generous dusting of grated Parmesan and a few broken pieces of walnut.