I learned this neat little trick the other day while making peanut butter cookies. (My husband says this recipe is addictive. I'm usually more of an oatmeal raisin person, but I have to grant that these are good.)

I imagine you could make ANY cookie heart-shaped this way, as long as it's the type that you have to flatten slightly -- that is to say, the type that doesn't flatten into a puddle all by itself while baking.

The trick is this: after flattening a ball of cookie dough with the palm of your hand (or bottom of a jar. Or whatever. You know,) just slice a small triangle out of one side and then pinch the opposite side into a point. You can kind of smooth out the "curves" of the heart with your finger, too, if you like.
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