East Sussex Fire & Rescue Service was contacted after residents heard the smoke alarm and noticed a strong smell of burning.
The flat in Turton Close, Bristol Estate, Brighton, was unoccupied at the time and crews from Brighton and Roedean were called out at 6.06pm.
Firefighters forced entry and tackled the blaze wearing breathing apparatus and used a carbon dioxide fire extinguisher (used when electrical equipment is involved with a fire).
Crews remained at the scene for an hour.
More than half of accidental fires at home are started by cooking.
Many kitchen fires happen when people are not paying attention or they leave things unattended.
Find out how to keep safe while you are cooking and what to do if a fire starts in your kitchen.