For salads, the leaves and flowers are the tastiest. The stems are best for pickling as a raw cultured vegetable. The whole plant (except roots) can be chopped and steamed.
Purslane contains high amounts of pectin (known to lower cholesterol) and nicely thickens soups and stews. It is delicious ingredient in a "wild green salad", using other greens like dandelion, miners lettuce and mallow.