Four fire engines and around 25 firefighters attended a fire on Bateman Street in Soho.
The fire occurred in a five-storey building made up of a pub on the ground floor with flats above. Part of the second and third floors were damaged by fire, along with ducting running between the second and fourth floors. There were no reports of any injuries.
The fire is being treated as accidental and is believed to have been caused by oil overheating in a deep-fat fryer in the kitchen of the pub.
A London Fire Brigade spokesperson said: "Cooking should never be left unattended on the hob or grill - if you have to leave the kitchen, turn off the heat.
“Cooking with hot oil can be really dangerous and the risk increases when you start frying food more than once. All it can take is for you to become distracted for a few seconds and your cooking oil can quickly go up in flames.
“Never fill a pan more than one third full of fat or oil and make sure food is dry before putting it in hot oil – oil and water are a dangerous mix.
“If the oil starts to smoke, it’s too hot so turn off the heat and leave it to cool. We also advise using an electronic deep fat fryer if possible – they have automatic temperature controls and are much safer.
"It's also really important to keep the hob, cooker hood and extractor fan clean too – built up fat and grease can ignite and cause a fire."
The Brigade received the first of 19 calls at 1513 and Control Officers mobilised crews from Lambeth, Chelsea and Dowgate fire stations to the scene. A 32-metre turntable ladder from Paddington Fire Station also attended and was used as an observation tower, providing the Incident Commander with a greater situational awareness of the incident.
The fire was extinguished by 1641.