How to Make It
In a medium bowl, whisk the 00 flour and the 1/2 cup of semolina flour with the salt. In another bowl, whisk the egg yolks with the olive oil and 1/4 cup of water. Mound the flour mixture on a work surface and make a well in the center. Add the beaten yolks to the well and gradually incorporate the flour with a fork, starting with the inner rim of the well and working your way out until all of the flour is incorporated and a soft dough forms. Knead the dough until smooth and elastic, about 10 minutes. Wrap in plastic and refrigerate for 1 hour.
Cut the dough into 8 equal pieces and cover with a kitchen towel. Lightly dust 1 piece of dough with semolina flour and flatten slightly. Run the dough twice through a pasta machine at the widest setting. Run the dough twice through successively narrower settings until it is 1/8 to 1/16 inch thick and 14 to 16 inches long. Lay the pasta sheet on a semolina-dusted baking sheet and generously dust with more semolina. Repeat with the remaining 7 pieces of dough. Keep the pasta sheets covered with a damp kitchen towel.
In a food processor, pulse the almonds with the garlic and olive oil until smooth. Add the basil and pulse until finely chopped. Add the Parmesan, the 1 1/4 cups of pecorino and the mascarpone and pulse until smooth. Season the pesto with salt and scrape into a large bowl.
In a food processor, pulse the tomatoes with their juices until almost smooth. In a large saucepan, heat the olive oil. Add the garlic and cook over moderate heat, stirring, until fragrant, 1 minute. Add the pureed tomatoes and the sugar, season with salt and bring to a simmer. Cook over moderately low heat, stirring occasionally, until thickened, about 30 minutes; keep warm.
Meanwhile, preheat the oven to 450°. Line 2 rimmed baking sheets with parchment paper. In a very large pot of salted boiling water, cook 2 pasta sheets until al dente, about 3 minutes. Using a slotted spoon, lift out the pasta sheets and let them drain slightly, then turn gently in the pesto to coat. Lay one of the pasta sheets on a prepared baking sheet and dollop 1/4 cup of the ricotta near one end. Fold one-third of the pasta sheet over the ricotta, then fold the rest of the sheet over onto itself. Repeat to fill the second pesto-coated sheet, then repeat the entire process with the remaining pasta sheets, pesto and ricotta. Cover the folded handkerchief pasta with foil and bake for 10 minutes, until hot throughout.
Spoon the marinara sauce into shallow bowls. Top with the stuffed pasta handkerchiefs, garnish with pecorino and serve.
Doppio zero (“double zero,” or 00) is a fine Italian flour available at specialty food shops and from amazon.com.