Cook the syrup until caramel is formed. If you use a thermometer, it should measure 160-165C. If not, make sure that you do not overcook the caramel - when it turns amber colour, reduce the heat to very low and remove before it darkens.
Remove from heat and cool for few minutes.
In a separate pan, bring the cream to boil. Add slowly to the caramel, stirring constantly until caramel dissolves. Set aside and let it cool.
Recipe by Moms & Munchkins at https://www.momsandmunchkins.ca/butternut-squash-muffins/