Bring a large pot of water to a rolling boil and add a pinch of salt. Add uncooked long pasta and cook until al dente, about 8-10 minutes. Reserve about 3 tablespoons of pasta cooking water before draining the pasta.

In a cold skillet, drizzle in the extra-virgin olive oil and mix with drained canned tuna, red chili pepper, and garlic. Place skillet over medium-low heat, stirring gently until garlic is fragrant, about 2 minutes. Add butter if using.

Once garlic is fragrant, add lemon zest, stirring briefly to combine. Pour in reserved pasta water and lemon juice. Mix thoroughly to create a sauce.

Add drained pasta to skillet with sauce, tossing gently to combine. Cook for an additional minute until heated through. Adjust seasoning with salt and pepper, and add more lemon juice if desired.

Plate the Canned Tuna Pasta while warm, ensuring it's coated in sauce. Garnish with Parmigiano-Reggiano cheese and serve immediately.