What's the easiest way to prep a bottle quickly, especially for night feeds?

This is what I do because I don't want my son to cry for too long otherwise he's wide awake. I put warm water in a flask & prepare 3 sets of milk powder (3 scoops each) and 3 clean bottles and place it next to my bed on my side table. Takes me less than 3 minutes to make his milk and I get to dreamfeed him which means I get my sleep back heehe

My friend used a flask. She'd boil the kettle before bed and leave it to cool for 30 mins then fill the flask. The water would then be at the right temp and would stay at that temp for up to 8 hours.

thanks