Heat 1/4 cup of the oil in a medium saucepan over medium heat.

Add garlic and cook for about 1 minute, stirring often until fragrant but not brown.

Add crushed tomatoes, stir and let cook for 20 minutes over low heat, stirring from time to time.

Meanwhile, bring a large pot of salted water to a boil over high heat.

Cook spaghetti until it just begins to soften, no more than 3 minutes. The pasta should not be fully cooked, not even al dente, as it will continue cooking once it is mixed with the sauce and baked. Save 1 cup pasta water, then drain pasta and rinse with cold water until cool.

Place in a bowl and add remaining 1 tablespoon oil.

Toss to coat, then set aside.

Season tomato sauce with salt and pepper, then add olives, sun-dried tomatoes and pepper flakes.

Cook for 10 minutes, stirring from time to time.

Let cool for a few minutes, then toss with pasta until well coated.

Add chopped parsley and toss again. If the pasta seems too dry, sprinkle with a bit of the saved pasta water to moisten it.

Spray one piece of parchment paper with cooking spray and fold the long side in half so it resembles a book.

Open the "book" and place one serving of the pasta mixture on the right-hand side.

Do not add extra sauce; if the pasta is too saucy, it will cause the parchment paper to tear.

Close the "book".

Starting with the bottom left corner, fold a small triangle with the tip going up and over the parchment paper.

Repeat again with another triangle that overlaps the first.

Continue turning up the paper in overlapping triangles, making sure that there is little space between the seals and the pasta, and folding the sides tightly to resemble a sealed half-moon shaped package.

Transfer the package to a baking dish and repeat process with remaining parchment paper and spaghetti mixture.

Bake for 10 minutes, then transfer to plates, open carefully with scissors and garnish with more parsley, if you like.