Who invented the Cooking ?

Invented by - Homo Erectus ("Upright Man")

Year - 1.8 million years ago approximately.

There are no exact clear evidence of when food was first cooked but most of the Scientists and Anthropologists believe that cooking was invented as far back as 1.8 million years ago. 

Famous Anthropologist, Wrangham proposed cooking was instrumental in human evolution, as it reduced the time required for foraging and led to an increase in brain size. He estimates the percentage decrease in gut size of early humans directly correlates to the increase in brain size. Most other anthropologists, however, oppose Wrangham, stating that archeological evidence suggests that cooking fires began in earnest only about 250,000 years ago, when ancient hearths, earth ovens, burnt animal bones, and flint appear across Europe and the Middle East. Two million years ago, the only sign of fire is burnt earth with human remains, which most other anthropologists consider to be mere coincidence rather than evidence of intentional fire. The mainstream view among anthropologists is that the increases in human brain size occurred well before the advent of cooking, due to a shift away from the consumption of nuts and berries to the consumption of meat.

Researchers at Harvard University traced the origins of cooking back through the human family tree after studying tooth sizes and the feeding behaviour of monkeys, apes and modern humans.

They concluded that cooking was commonplace among Homo erectus, our flat-faced, thick-browed forebears, and probably originated early in that species' reign, if not before in more primitive humans. "This is part of an emerging body of science that shows cooking itself is important for our biology; that is, we are biologically adapted for cooking food," said Chris Organ, an evolutionary biologist at Harvard.