Bring a large pot of salted water to a boil, and cook the pasta according to package instructions to achieve an “al dente” consistency. Drain the pasta and set aside, reserving some of the water.
Meanwhile, slice out the center rib of each collard green. Stack the greens on top of one another, and roll them up like you would a sleeping bag.
Slice across the roll of collard greens thinly, about 1/8” apart. Unravel the rolled collard greens to reveal long, strand-like strips. Feel free to chop the strands a few times if they seem too long.
Set a large sauté pan over medium heat, and add the olive oil. Toss in the collard greens, garlic, and red pepper flakes. Sauté until the garlic is fragrant, about 2 minutes.
Add the cup of hot water to the pan and bring to a simmer. Cook until the collards are tender and a majority of the liquid has reduced, about 7-10 minutes.
Remove the pan from the heat, and add the cooked spaghetti and a tablespoon or two of the reserved pasta water, tossing well with tongs to combine. Season with salt and pepper.
Serve with an extra drizzle of olive oil and shaved Parmesan, and enjoy!