When you get your purslane home store it, wrapped in a dishtowel, in a plastic bag. Before eating it, wash it well. Purslane grows really close to the ground so it can be super-sandy. If the stems are thin and not too fibrous (they should snap easily - like a fresh green bean) you can use them. If the stems are tough or stringy, strip the leaves from the stems and just use them.
I like using purslane fresh in salads like this one here. It's a succulent leaf that holds up well to citrusy dressing and chunky partners like this summer squash. I chopped my bunch of purslane into 1/2" lengths and tossed it with sliced summer squash, chopped jalapeno and a lemon dressing.
In addition to using it fresh, you can quickly sauté the stems and leaves with garlic and chili. I have also pickled purslane stems and they're a great addition to a sandwich (use a dilly bean recipe).
This Summer, I am chronicling my first CSA (Community Supported Agriculture) experience. My CSA share is from Arrowhead Farm, a farm based in Newburyport, MA. Each week, I am posting about what was in my share and what I'm doing with it. By way of full disclosure, I won my share through a raffle and am not paying for it. However, Arrowhead did not know I was entered in the raffle, and I received no special consideration because of this blog. I paid for my livestock share. A full set of all the photos I've taken of this share is here.