This is the extract version of Boston Lager. I never made this but the calculations are correct and sould taste very close.
Steep crystal in 1/2 gallon of 150f water for 20 min.Strain the grain and run 1/2 gallon of 150f water over the grains.Add enough water to get 1 1/2 gallons. Bring to a boil and remove from jeat. Add the Xtract,light DME, and bittering hops. Bring water to 2 1/2 gallond and boil for 45 min.Add flavor hops and irish moss. Boil for 13 min. and add the aroma hops.Boil for 2 more min. Remove from stove, cool,place in fermentor,and add enough water to make 5 gallons.Pitch yeast and ferment cool(55f).Rack to secondary and add the dry hops.