How to Make It
Put the ricotta, spinach, egg yolk and olive oil in a food processor and process to a paste. Add the flour, semolina, salt and white pepper and process until the mixture comes together to form a ball. Scrape the dough out onto a lightly floured work surface and knead briefly. Wrap the dough in plastic and let stand at room temperature for 30 minutes.
Cover the sun-dried tomatoes with hot water and let soak until plumped, about 25 minutes. Drain well and coarsely chop, then transfer to a mini-processor and puree.
Heat the oil in a saucepan. Add the fresh tomatoes and garlic and cook over moderate heat, stirring, until the tomatoes release their juices, about 3 minutes. Add the basil and Chicken Stock, cover and simmer over low heat until the tomatoes are very soft, about 5 minutes. Strain the sauce, pressing on the tomatoes to extract as much sauce as possible. Stir in the sun-dried tomatoes and season with salt and black pepper.
Cut the cavatelli dough into 10 equal pieces. On a lightly floured work surface, using both hands, roll out each piece of dough into a 1/2-inch-thick rope. With a fork, cut the rope into 1/2-inch pieces. Press the side of the fork lengthwise into the center of each piece. Set the cavatelli on a lightly floured baking sheet.
In a large pot of boiling salted water, cook the cavatelli in batches, stirring, until they rise to the surface, about 4 minutes. Drain the cavatelli and divide them among 8 shallow bowls. Pour 1/2 cup of the hot tomato sauce over each portion and sprinkle each with 1 teaspoon of the Parmesan cheese.