Use a sharp small knife & sorta just push the knife until you hit the gravel/feed sack. Imagine a half flattened football...I like to start one on of the ends (top/bottom) cutting along the line of most outer side tip to tip. Then just muscle it apart in half & pick/peel the sack-o-crap out.
They are good but chewy when cooked along side the hearts & still like them...my mom uses the pressure cooker & gets them tender I'm looking into.
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