Lieutenant James Adamson was awarded the Military Cross after killing two insurgents during close quarter combat in Helmand's notorious "Green Zone".
The 24-year-old officer, a member of the 5th battalion The Royal Regiment of Scotland, revealed that he shouted "have some of this" before shooting dead a gunman who had just emerged from a maize field.
Seconds later and out of ammunition, the lieutenant leapt over a river bank and killed a second insurgent machine-gunner with a single thrust of his bayonet in the man's chest.
The officer was one of 145 members of the armed services who last week received awards in the latest Operational Honours list.
In a graphic description of the intense fighting in Helmand, the officer told of the moment killed the second fighter. He said: "It was a split second decision.
"I either wasted vital seconds changing the magazine on my rifle or went over the top and did it more quickly with the bayonet.
"I took the second option. I jumped up over the bank of the river. He was just over the other side, almost touching distance.
"We caught each other's eye as I went towards him but by then, for him, it was too late. There was no inner monologue going on in my head I was just reacting in the way that I was trained.
"He was alive when it went in ? he wasn't alive when it came out ? it was that simple."
Recalling his feelings in the moments afterwards Lt Adamson, said: "He was young, with dark hair. He only had kind of whispy hair on his chin, not a proper beard, so he wasn't that old, maybe a teenager.
"Afterwards, when he was dead, I picked up his PKM (Russian-made belt-fed machine gun) machine gun and slung it over my back.
"We then had to wait for more of my men to join us. We thought there could be more Taliban about and we were just watching our arcs of fire, waiting for more to come out of a big field of maize which came right up to the river we had been wading through.
"One of my men, Corporal Billy Carnegie, reached us, looked at the two dead Taliban on the ground and then saw the blood on my bayonet and said "boss what the **** have you been doing?"
