Striker Jon Daly scored twice, while Lewis Macleod, Andy Little, Robbie Crawford and another new arrival Nicky Law were all on the score sheet as well.
McCoist said: "I'm delighted. The best way I feel we show teams respect is to play them in the same manner. It couldn't have been any better.
"It's important as we need to get goals and confidence in the team and give the rest of the teams a reminder that if they are not up to scratch we will punish them.
"If you are not up to doing your job you will be punished. The level of commitment and skill over the 90 minutes was really pleasing.
"We have been delighted with the boys we have got but won't get carried away."