Need shortbread recipe for mold pans

So I got these cockle shell pans presumably designed for madeleines and they work a treat that way. But would love to make sandwich cookies, which would mimic the look of whole clams. Found a few recipes for that but the texture of the cookies produced all seem kinda bubbly/flakey; am looking for something that will produce a tighter, smoother crumb, to better counterfeit the surface of a real seashell. I'd glaze the finished product like abalone, natch. ;-)[This is the general idea of what I'm after, minus the linen and pearls.

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Ships in approximately 5-7 business days, This beautiful Stoneware Shortbread Pan with will have you baking impressive shortbread cookies to amaze

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