Preheat oven to 180 degrees Celsius.
In a bowl, mix together flour, sugar and salt.
Mix in the instant yeast and set a side.
In a saucepan, heat together the water, milk and butter until the butter melts. Set a side to cool to lukewarm.
Add egg and lightly beat until incorporated. transfer the wet mixture into your mixing bowl.
Add the dry mixture and mix using your stand mixer with dough hook attachment for 9 minutes.
Transfer the dough on a lightly flour dusted cleaned surface and knead for 3 minutes or until the dough is done. Shape the dough into sphere and rest for 3 minutes. Transfer the dough in a bowl and cover with a cling wrap and proof in a warm environment for an hour or in the fridge overnight.
If proof in the fridge, bring it out of the fridge at least an hour to thaw.
Lightly punch the dough and transfer on a lightly floured cleaned surface. Flatten the dough to 24 by 18 inch rectangle using your rolling pin. Spread the Butter Sugar mixture.
Starting at the lower end, fold the dough into three part towards the center. Cut into 1.5 inch wide to make 16 strips and roll each strip. Transfer in a muffin pan. Cover with a clean kitchen towel and let it rest for 30 minutes.
Pour half tablespoon of the heavy cream on each cinnamon bun dough and bake for 17 minutes. Transfer in a wire rack to cool.