What is this leafy green with a sharp taste, and how do I safely use/cook it?
From the photo &amp; description of the leave look &amp; feel, these sound like green wave mustard--a variety of mustard greens with curly leaves.
Mustard greens have a &quot;spicy&quot; or peppery taste, which also seems to align with your experience.
Mustard greens can be safely eaten raw or cooked. It can be a raw salad ingredient, or be sauteed, braised, grilled, etc. Because of the assertive flavor, some people find it best when mixed with other leafy greens to balance out that spiciness you describe.