This weekend I attempted to make this recipe for brioche.  I did the first step and combined the the milk, yeast, 1 egg and 1 cup of flour which caused very big clumps and then I added the sugar.  I then did the 2nd through the 5th steps but the clumps stayed and the dough was really wet (like pancake batter) so I tried adding more flour until I got something like the right consistency. I then covered the dough and put it in a draft free area that was warm for 2.5 hours but my yeast did not rise and the dough still had clumps in it. I waited longer but nothing so I had to throw it away.  I really wanted to try this recipe again so I would appreciate any insight into what I did wrong.   
Well 1.5 cups is volumetric so the weight will depend on how tightly packed that cup is, if they are chopped, etc.  On average though, 1.5 cups of chopped hazelnuts is about 6.08 oz (172 g) according to the USDA's averages.  You can check the USDA's National Nutrient Database page for hazelnuts if you want to see estimated weights for 1.5 cups of whole, chopped, or ground hazelnuts. 