There could be couple of reasons why your beer bread turned out tough. Too much flour can cause the bread to be too dense and hard. Another reason could be that you stirred the batter too much. Quick breads rely on the chemical reaction that occurs when baking powder is mixed with a liquid. If you stir the batter too much, the gases will be released before the bread is even in the oven, and the bread won't rise. One reminder: Be sure your oven is preheated before you stir the bread ingredients together.