Place a heavy, dark baking tray or large cast iron pan in the oven. Preheat the oven to 450 F.

(Optional - if serving pasta) Bring a large pot of salted water to a boil on the stovetop. Once the water reaches a rolling boil, add the dried pasta and cook until al dente, per the instructions on the package.

Separate the radish greens from the roots and set aside. Gently wash the radishes, then slice in half (from stem to root).

Toss the radishes with the about 1.5 tbsp of olive oil, and a little salt and freshly ground pepper.

Carefully remove the tray/pan from the oven (it will obviously be very hot). Working quickly, layer the radishes, cut-side down, onto the hot surfaces. Return the tray/pan to the oven and bake for 10-12 minutes, or until the radishes are browned, softened, and fairly wrinkled looking on the surface.

Thoroughly wash the radish and parsley greens. Combine the greens, garlic, and pistachios in a food processor and puree. Scrape down the sides a few times and try to crush/chop the greens as thoroughly as possible.

Once the greens/nuts/garlic are very well chopped, add the cheese. I add it in large pieces and let the blades do the work, which yields lots of little chunks of cheese (which I quite like). For a more uniform pesto, pre-shred the cheese.

Once the ingredients are very well mixed, add the lemon juice and olive oil and puree again, until the mixture just combined and fairly smooth. Don't process too long, as the olive oil can become bitter. Add salt to taste and, if you like, extra olive oil and/or lemon juice.

Serve the roasted radishes and pesto with the cooked pasta (if using), toast, fresh bread, polenta, couscous, or anything else you can think of that you'd enjoy.