The present invention relates to a method for producing an extruder cooked food product based solely on oat components, wherein previously non-heat treated, de-hulled oat grain is first dry milled into an endosperm-starch rich oat flour, containing active enzymes, and thereafter, mixed with oat dietary fibre, protein and oil derived from oat grains. Preferably the oat dietary fibre, oat protein and oil are obtained from oat grains that have not previously been heat/treated. If required the mix is mixed with water to form a slurry having a dry matter content of 60%-90% (w/w), said slurry is thereafter cooked in an extruder cooker and extruded to form an expanded food product having a crispy and puffed texture, said method inactivating all enzymes active in the endosperm-starch rich flour and slurry mix.
