2 pounds fresh tuna scraps or steaks, cut into large chunks
10 ounces pancetta, cut into medium dice
6 ounces mackerel, cut into large chunks
3 tablespoons olive oil
1  onion, diced
4 cloves garlic, crushed
1 bottle red wine (750 milliliter)
1  bay leaf
1 teaspoon red pepper flakes
1/2  {cinnamon stick} (about 2 inches)
1 can (28 ounces) whole peeled tomatoes and their juice
 sea salt
 freshly ground {black pepper}
1 pound dried rigatoni (preferably DeCecco)
1/2 pound mascarpone cheese

In a food processor, pulse the tuna, pancetta, and mackerel until coarsely ground. Set aside.

In a Dutch oven, heat the olive oil over a medium flame. Add the onion and garlic and cook, stirring occasionally, until translucent, 3 to 4 minutes. Add the ground tuna mixture, and increase the flame to medium high. Cook, stirring with a fork, until all the juices are dry and the bottom of the pan begins to brown, 7 to 10 minutes. Add the red wine, bay leaf, red pepper, and cinnamon stick, and cook until dry, about 15 minutes. Add the tomatoes, crushing them by hand, and their juice, and 1/2 cup water. Season with 1 teaspoon salt and 1/2 teaspoon black pepper. Let simmer, uncovered, for 1 1/2 hours. The sauce should be moist, not wet. Taste and reseason with salt and pepper. Discard the bay leaf and cinnamon stick.

Prepare the rigatoni according to package directions, cooking 1 minute less than the package instructs for al dente. Drain in a colander and combine with the Bolognese sauce. Divide among four serving bowls. Top each bowl with 1/4 cup of mascarpone, a sprinkling of salt, and a grinding of pepper.