The Biscuit and the Yam

A wee little biscuit softly implored a gruff, hard-hearted and tuberous yam, "oh, why, my dear friend, must you be so hard?" and the yam replied, "I am what I am!" "In my kitchen, I will not have this chat", I said, as, into the oven they went. "Now I'm soft", said yam, an hour after that. "But I'm hard", I heard from the oven vent, "...if, my dear yam, I might beg your pardon, while this heat made you warm up and get soft, I had to wait, and burned up to harden", said the biscuit as the black smoke did waft. Poem idea? Don't make my mistake, or you will burn your house down while you bake.