Spinach with Black Pepper and Garlic

Here is your template for cooking both leafy greens and stemmy greens, quickly and deliciously. This is a streamlined pahk boong fai daeng, the classic stir-fry of a slender, hollow-stemmed vegetable known as pahk boong in Thai and as ung choy, kang kong, water spinach, and morning glory, among other names.

A wok is handy for corralling the potential avalanche of raw spinach leaves before the heat shrinks them down to a plateful, but a large, deep skillet will work. Having two long-