I had a blast making this for dinner. I decided I wanted something really herby and gathered what I could find in the yard — plus lots of Swiss chard from our overflowing green garden! In addition to the chard, I picked dill, basil, mint, and rosemary.
The sour cream is optional, but it's a nice addition if you happen to have it lying around, since it makes the dressing a bit more "saucy" in consistency.
Bring a large pot of water to a boil over high heat. Cook the pasta according to package directions. Place the chard in another large pot with 2 tablespoons water over medium heat and cover with a lid. Steam until just wilted, about 3-5 minutes.
Drain the pasta and combine with the chard, pesto, tomato, and sour cream, if using. Toss in the mixed herbs and serve.