Bring a large pot of salty water to boil. You want the water to be extra salty to mimic the fresh ocean seafood of Italy—I add ¼ cup salt to 5QT of water. Meanwhile, roughly chop the parsley leaves (setting aside the stems for later) and 4 garlic cloves.
In a large sauce pan heat ¼ cup olive oil on medium-low. Zest 1 lemon straight into the pan, then add chopped garlic and whole parsley stems. Give it a good stir and cook until fragrant, about 1 minute. Your whole kitchen should smell of lemony garlic.
Add 700g whole cherry tomatoes and turn heat to medium-high. Cook the cherry tomatoes until they burst, about 15 minutes. Use the back of a wooden spoon to crush the tomatoes, releasing their juices, to form a rustic sauce. Around this time, drop your pasta and cook to al dente by following package instructions.
When most of the tomatoes have burst, add 750g mussels and bring to a boil. Cover and cook, occasionally shaking the pan, until the mussels have opened. Remove the mussels and set aside. At the same time, remove and discard the parsley stems.
Transfer the cooked pasta to the sauce pan along with ¼ cup pasta water. Stir until the sauce has emulsified and the pasta is evenly coated. Finish with chopped parsley before giving it a final toss. Serve pasta topped with mussels and resist the urge to add parmesan—I swear it doesn't need it!
