Originally Posted by simple-stupid
Well I only have one packet right now, and would prefer to not go back to my lhbs, is there anything I could do? (besides just under pitching)
I suppose you could make a starter with it. I know most people do not recommend starters for dry yeast, but I cannot think of any reason it would not work. Yeast is yeast, after all. If you rehydrate your yeast and make a 1 liter starter, I do not see any reason why it would not work just like liquid yeast. (If I am wrong here, someone with more experience in this area please correct me!) I think that the reason most brewers do not do this is because dry yeast is very affordable, and 2 packs is more than enough yeast for any 5 gallon batch you are likely to make.
If you do just under-pitch, it will probably still work, but I would give it plenty of oxygen at pitching, and an extra week or 2 to ferment/clear/condition. I underpitched my first big beer (a 1.080 Belgian Tripel) by using only one pack of dry yeast, and it still turned out fine, but funky yeast flavors from stressed out yeast are not considered unusual in Belgian styles!
"Give a man a beer, and he will waste an hour. Teach a man to brew, and he will waste a lifetime!" Bill Owen