There is evidence humans were using fire to cook food as far back as 800,000 - 1m years ago, flavouring this food with spices is a little shorter at 6-8000 years, all those generations having to put up with plain food!
Luckily we get such a wide variety of flavours from the around the world to flavour an even greater number of cuisines from all manner of cultures, they all started with the first one, shame we will never know what that truly is