Bring a pot of water with 1 teaspoon of salt to a boil, and cook the pasta until al dente.
Drain, but reserve about 1/2 cup of the pasta liquid.
Place the pine nuts on a baking sheet in the oven at 350 degrees Fahrenheit for about 10 minutes. Shake the pan after about 5 minutes to turn. When they are done, remove from the oven and set aside.
While the pine nuts are toasting, heat the olive oil in a large skillet over a medium high setting. Saute the garlic for about 2 minutes, until fragrant.
Add the tuna, lemon juice and zest, and continue to cook for another 2 to 3 minutes to blend flavors.
Now add the cooked pasta, herbs and seasonings – reserving a little of the parsley to garnish – stirring them around until thoroughly blended in the pan. Add the reserved pasta water to thin out the sauce if required to coat the pasta thoroughly.
Divide between four plates, top with grated Parmesan, and garnish with the reserved parsley.