I start the slicing process in the prep before the cook. While prepping I take note of the grain structure. I make a small nick of a cut across the grain on the corner of the Flat. After the rest I use the back of my knife to separate the Point from the Flat. I then locate the nick and slice as much as I need of the flat in 1/4" slices.( I normally give this portion away and rarely slice it except for 1 slice from corner)
The Point I rotate 90 deg and cut it in 1/2. This puts the first cut across the grain, then I slice as much as I need in 3/8"slices.
Slicing the whole brisket at one time will dry it out in short order and make it difficult to reheat with out drying it out completely.
The alternate method I use if serving the whole packer to a large crowd is cut to order. I will locate the thinnest part of the point and cut the brisket strait across in that area then I rotate the point 90 deg as above, locate the nick in the Flat and start to cut as needed.
The difference in the two methods is because I normally give my Flats away and keep the Point. Doing it that way I get all the Point and the lucky recipient gets the complete Flat.
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