In a medium size pot melt the butter, then add the water, sugar and chopped peeled apples.
Stir and cook for about 3 minutes over medium/high heat just until the sugar has melted, then lower the heat to medium/low and continue cooking and stirring often for about 8-10 minutes, add the cinnamon in the last couple of minutes. The apples should be tender and the sauce a golden brown colour.
Move to a clean glass jar, let cool or use warm. Once it is cool it should be refrigerated, the longer it sits the thicker the sauce will become. Enjoy!