Whisk together the warm water, tomato passata, tomato paste, and 1 teaspoon of sea salt in a medium saucepan over low heat. Keep warm at a very gentle simmer throughout cooking.

Heat the extra virgin olive oil in a wide, heavy-bottomed cast iron or carbon steel skillet over medium-high heat. Add the minced garlic and crushed red pepper flakes, sizzling for 45 to 60 seconds until fragrant without scorching.

Carefully pour half a ladle of the warm tomato broth into the hot oil—it will bubble and splatter vigorously. Immediately lay the uncooked dry spaghetti flat across the skillet in an even layer.

Allow the spaghetti to fry undisturbed for 3 to 4 minutes until the bottom strands begin to toast, brown, and lightly stick to the pan surface.

Using a sturdy metal spatula or tongs, gently turn and redistribute the pasta to expose uncooked strands to the pan surface. Ladle 1 to 2 scoops of hot tomato broth over the spaghetti, scraping the browned bits from the pan bottom.

Continue cooking in stages, adding 1 ladle of broth at a time only after the previous liquid has completely reduced and the pasta starts sizzling in oil again. Let each batch char slightly before adding more liquid, repeating until the spaghetti is chewy and al dente with dark, crispy edges.

Remove from heat as soon as the sauce is fully reduced and clings tightly to the glistening, charred noodles. Taste, add remaining salt if necessary, and divide immediately onto warm plates.