THERE OUGHTA BE A LAW against canned green beans. Frozen beans aren't much of an improvement. For this dish, it must be fresh beans only (uncooked beans should snap easily). If in season, use fresh plum tomatoes. Otherwise, canned diced tomatoes are entirely suitable (Muir Glen and Progresso brands are especially good).
To prepare the beans, wash and drain; then trim off the ends. You can improve the presentation by slicing supermarket-sized beans in half lengthwise; if you do, watch the cooking carefully so that they don't get mushy.
For a spicier dish, include the optional chile peppers to taste.
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