It is a common misconception that when cooking with alcohol, the alcohol burns off.  This is not true. Some alcohol almost always remains.  If you are a recovering alcoholic or if you have to test for your work, you will find the following chart from the U.S.D.A. helpful.

Now, you should keep in mind that the percent listed in the chart below, is a percentage of the amount of alcohol that was in the particular beverage to begin with.  Most spirits, (ie. whiskey, bourbon, vodka, gin, brandy, rum etc.) around 80-proof, or about 40% alcohol.  So, according to the chart below, if the brandy you flame over your Crepe Suzettes began with 40% alcohol, after being flamed it will retain 75% of the original 40%.  I’m no mathematician.  You do the math.  On the other-hand, let’s say you’re going to make a pot of beans