Warm the heavy cream and evaporated milk for the dough portion of the recipe in a small saucepan (don't let it get hot!) If you're using active yeast, add it to the warm milk/heavy cream and let it sit for 10 minutes. If you're using instant yeast, you can just mix the dry yeast with the flour and salt.
In a separate mixing bowl, combine the butter, eggs, sugar and vanilla extract. Add the warm milk/cream mixture, mix it until it's combined with the other wet ingredients and then add the flour.
Using a dough hook, knead until the dough forms and pulls away from the sides of the bowl. If you're not using a mixer, you'll need to knead the dough by hand for 2-3 minutes. The dough should feel slightly tacky, but not sticky.
Gather the dough into a ball and place it in a clean, greased bowl. Cover the bowl with a kitchen towel and let it rest for 1 and ½ hours. The dough will double in size as it rests.
While the dough is rising, make the filling by combining ½ of a cup of brown sugar with 3 tablespoons of cinnamon and 8 tablespoons of softened butter. Mix until it's all smooth.