I spotted fresh, small, crispy spinach leaves (spinacia oleracea) today at the Happy Green Cooperative's organic store on the second floor at the sabzi bazaar. A pack sells for Nu 15 only.
The trick is not to overcook the leaves. They are delicious when stir fried rapidly with slices of purple onion, garlic, black pepper and olive oil. The fresh leaves can also be eaten raw and are quite refreshing in vegetable salads. Just make sure they are thoroughly washed.
Update: Apparently, a popular myth among the Dutch is that reheated spinach is dangerous to your health. Today was the first time ever I heard about it. It's an urban legend. Please tell your friends from the Netherlands not to worry about it.