You could vary the pasta with large pasta shell or manicotti if you like. Leave out the dried porcini mushrooms or substitute 1 cup blanched spinach that has been well drained and then chopped.
Place olive oil in a large heavy-bottomed pot over medium heat. Add the onions and cook until onions are soft, about 2 minutes. Add garlic and cook until soft, about 1 minute. Add tomatoes and cook until mixture thickens to a rich-textured sauce, about 15 to 20 minutes. Season the sauce with salt, pepper and basil and parsley.
Drain the soaked porcini from water.
Heat 1 tbsp butter in a medium sauté pan over medium heat. Add onion and sauté for 2 minutes. Add mushrooms, garlic and continue to cook for 2 more minutes. Remove from heat. Let cool to room temperature.
Place the mushroom and onion mixture into a food processor. Blend until finely minced. Transfer to a large bowl. Add ricotta, egg, Parmesan cheese, tarragon and parsley to the bowl. Stir to combine. Cover and refrigerate until ready to use.
Preheat oven to 375 degrees F.
Add pasta to a pot of boiling salted water. Cook pasta until al dente, about 3 minutes. Transfer to baking sheet and cool slightly – don’t overlap the pasta sheets or they will stick together.
Lay pasta sheets flat on work surface. Add filling to a piping bag or just spoon filling onto pasta sheets. Divide the filling evenly among the 8 sheets, putting the filling in a line sothe sheets can be rolled up into a cigar shape. Roll up the pasta sheets and place the cannelloni into an oiled baking dish seam side down.
Pour the sauce over the cannelloni. Sprinkle with parmesan cheese. Cover with foil. Bake in preheated oven until hot and bubbling, about 30 to 35 minutes.
Let stand for 5 minutes before serving. Garnish with parsley and chives. Makes 8 cannelloni.