Six fire engines and around 40 firefighters were called to a fire at a house on Western Road in Plaistow.
Most of a garden and half of a ground floor mid terraced house was destroyed by fire.
The Brigade was called at 2101 and the incident was over by 2235.
Fire investigators believe the fire was accidental and caused by unattended cooking catching alight.
A London Fire Brigade spokesperson said: "Fires are more likely to start in the kitchen than any other room in the home.
"This incident is a timely reminder to make sure you never leave cooking unattended. If you do have to leave the room, turn off the heat."