What's the best way to crack open a Brazil nut without breaking the nut?
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Freeze Brazil nuts, or soak them in water for several hours before cracking.

Stand frozen nuts with the point facing up and hit with a hard object, such as a hammer, to crack.

Crack soaked nuts with a nutcracker. Place the nut in the grip of the nutcracker so that the seam of the shell is subjected to the direct force.

Use minimum force necessary to split the shell when squeezing, in order to avoid crushing the nut kernel inside. Rotate the nut while squeezing so the shell cracks slowly.

Extract the kernel from the shell.

Allow the kernels of soaked nuts to dry for a few hours after cracking.

Read more: How to Crack Nuts | eHow.com http://www.ehow.com/how_10768_crack-nuts.html#ixzz16j8GzCOo