The invention relates to a flour based food product comprising a thermostable .alpha.-amylase and in-situ modified starch, as well as to a process comprising the steps of making a batter by mixing at least flour, water and a thermo-resistant .alpha.-amylase and cooking the batter on at least one hot surface, to the use of thermostable .alpha.-amylase to manipulate textural attributes of flour based food products, and to a method for modifying starch in a wafer without increasing batter viscosity. Preferred flour based food products are wafers, biscuits and crackers.