Dissolve yeast and 1 tsp granulated sugar in the warm water. Stir until dissolved and let sit for a few minutes until a foam starts to form on top. See notes if a foam doesn’t form.
½ cup warm water, 1 package yeast, 1 tsp granulated sugar
Sift the flour into a large bowl and make a well. Add the yeast mixture and the rest of the ingredients into the well. Mix until a sticky dough forms and the flour is incorporated. The dough will be very wet and sticky. If it is too wet and doesn’t resemble a dough, add a bit more flour. It will be less sticky after rising.
5 cups all purpose flour, ⅓ cup granulated sugar, ¾ cup butter, 2 eggs, 1 tsp vanilla extract, ¾ cup warm milk, ⅛ tsp sea salt
Cover with a damp cloth and place in a warm area to rise for about 30 minutes, or until doubled in size (see notes).
While the dough is rising, mix together all of the cinnamon filling ingredients to form a paste. Set aside for later.
⅓ cup butter, ½ cup brown sugar, 2 tbsp cinnamon
Prepare baking pan by buttering with a pat of butter or greasing with cooking spray.
Punch down the dough and fold a few times to mix. On a lightly floured surface, and roll out to a 18” by 24” rectangle. Spread the cinnamon filling evenly over the dough all the way to the edges. Spread the blueberry filling over top, leaving an inch around the edges. Carefully roll starting at the short side to make a long sausage. Careful to not let too much blueberry filling escape.
Cut the roll into 12 even pieces using unflavoured floss or sewing string. Wrap the string all around the roll and pull to cut.
Arrange the pieces into the pan, spooning any blueberry filling that leaks out back into the rolls. Let the rolls rise in a warm place until puffy and increase by a third of their size.
Place the rolls into the oven and heat the oven to 180°C (350°F). Bake for 25-30 minutes or until the rolls are golden brown on top. Let cool inside the pan until warm.