Creamy, fresh, and green with some pop of umami richness from mushrooms and olives and a little crunch from sunflower seeds. This pasta hits all the marks for an easy, decadent, but not overly heavy, quick pasta (if you have some pesto already, though still pretty quick if you don’t.) you can start the water for your pasta while you prep you other ingredients, halfway through your cook time for your pasta you cook the mushrooms, olives and sunflower seed and then toss everything together when the pasta is done. This dish is a prime example of why i always say to make extra pesto to have on hand, it makes for super quick delicious meals and it doesn’t take much extra time to make a double or triple batch of pesto.
Here are our participants for this round, cavatappi, thinly sliced cremini mushrooms, chopped kalamata olives, sunflower seeds (raw and unsalted), ricotta (dairy or non-dairy), and watercress+herb pesto. Now, for the pasta, cavatappi is the top choice here, its shape and texture work well to hold the pesto and ricotta and kind of ensnare the other ingredients, you can sub any other textured pasta, but i wouldn’t recommend smooth pasta as the sauce won’t stick as well and have a tendency to just sort of slide off your noodle. Ricotta brings creaminess and body without heaviness, the pesto brings bright, vibrant, green notes, mushrooms for some texture and umami, olives for little bursts of intense briny meatiness, and sunflower seed provide a nice lightly crunchy texture, as well as bringing their own nutty richness to the dish.
Thinly slicing the mushrooms allows them to sort of wrap around the noodles like a blanket and prevents their flavour from overpowering any individual bite, instead of dominating, they enhance. You want to sautee them just long enough to get some brown on them, then toss in the sunflower seed and continue to cook until they are also lightly browned and toasted. The olives get tossed is the pan last and simply stirred in. 
When the pasta is done, simply take a cup of the pasta water and throw into your pan, then drain your pasta and toss it into the pan and cook until the liquid is mostly gone, then remove from the heat, and add in your ricotta and pesto. Toss, stir, flip, cast a spell, whatever you have to do to mix everything up, salt to taste and serve it up with a light (or heavy) dusting of fresh ground black pepper on top. That’s it. It is done. Finito. See? i TOLD you it was super easy and quick!
Now, while watercress+herb pesto is obviously the number one choice here (after all, the recipe has it in the name!) you can use any green pesto here, HOWEVER, if it is a stronger flavoured pesto (such as basil) then start with half the amount of pesto and add more if you’d like, otherwise it might be quite overpowering. Some non-green pesto would be quite lovely this way as well, sun-dried tomato would be quite rich and decadent, again i’d suggest starting with half the amount and adding more if you want as these tend to be much stronger in flavour.
If you only have roasted sunflower seeds on hand, they are perfectly fine to use, simply skip cooking them and add them along with the olives, if they’re also salted, simply add less salt.
Now, stop reading, go forth and mangia!