Combine the diced tomatoes, diced onion, kosher salt, Aleppo pepper, and 2 tablespoons extra virgin olive oil in a large bowl and toss to combine. Refrigerate until needed.

Place the chicken in a large pot (see Note 1) with the garlic, 2 teaspoons kosher salt, and 10 cups of water. Add more water if needed to ensure the chicken is covered by 1 inch.

Bring to a boil. Reduce the heat and simmer, uncovered, for 30 to 40 minutes, or until the chicken is cooked through and can be shredded easily. Periodically skim any foam from the top of the water.

Carefully remove the garlic and transfer to a small bowl to cool. Remove the chicken from the pot and transfer to a bowl. Once the chicken is cool enough to handle, pull the meat from the bones and shred it. Discard skin and bones or reserve for stock, if desired.

Once the garlic is cool enough to handle, carefully pop the cloves from the paper and mash them into a paste.

Skim off any remaining foam or scum from the pot. Replenish the pot with enough water to cook the pasta and add 1 teaspoon kosher salt. Return to a boil. See Note 2.

As the chicken boils, add the bowl of tomatoes to a wide, ovenproof pot and turn the heat to medium. Once the tomatoes come to a boil, reduce the heat to medium-low. Simmer for 10 minutes until the tomatoes begin to soften. Add 2 tablespoons tomato paste and the reserved garlic paste and stir until smooth and incorporated. Taste and season with a pinch of sugar, more kosher salt, or more Aleppo pepper, if desired.

Reduce the heat to low and continue simmering, uncovered, for 30 minutes until the onions are soft and the sauce is thick and jammy. Add a splash of water as needed to prevent the sauce from sticking.

Once you’ve shredded the chicken, add it to the sauce.

Add the pasta to the pot of boiling water and cook according to package directions. Scoop out ¼ cup of the liquid before draining the pasta.

Turn on the broiler. Add the cooked pasta and reserved pasta water to the pot and toss to coat. Turn off the heat and scatter the shredded mozzarella on top. Transfer to the broiler for 2 to 3 minutes until browned and bubbly. Remove from the oven and scatter the fresh basil leaves on top. Finish with a few cracks of black pepper, if desired.

Divide the pasta between bowls and serve with more basil, if desired. Enjoy!