In a small saucepan, heat the milk to 115-120 degrees F over medium low heat, about 2 minutes, until steaming but not boiling. Pour the warmed milk into the bowl of a stand mixer with the hook attachment. Add the 2 Tablespoons of the granulated sugar and the yeast package. Let the mixture sit until it starts to foam, about 5 minutes.
Add the remaining sugar, softened butter, and egg and mix at low speed for about 1 minute. Add the flour and salt to the mixture and mix until the dough comes together for about 2-3 minutes.
Continue to mix/knead over medium speed for another 2-3 minutes. The dough should be soft and a bit tacky but not stick to the sides of the bowl. If the dough is too sticky, add one teaspoon of flour.
Remove the dough from the bowl onto a silicone mat, if needed shape it into a ball. Place the dough in a large bowl that has been lightly oiled (no more than 1 tablespoon of vegetable oil in the bow). Cover with plastic wrap or a kitchen towel and let rise at room temperature until doubled in size, which could take 1 ½ to 2 hours, depending on the weather.
Blueberry Filling
While the dough is rinsing make the blueberry filling by placing the blueberries, sugar and lemon juice in a sauce pan over medium heat. Stirring frequently to smash most of the blueberries and dissolving the sugar (leave some whole for chunky texture). Cook, stirring frequently for about 10-12 minutes until it thickens. Remove from the heat and cool completely. Once cooled, stir in the lemon zest.
Grease the bottom of a large cast iron pan or 9x13 baking dish.
Punch down the dough and turn it out onto a lightly floured surface. Using a rolling pin, roll the dough out until it is about ½” thick and about a 12” x 18” rectangle.
Spread the cooled blueberry mixture, leaving a small amount of space along the long edge of the dough to start the roll.
Roll up the dough tightly and then cut into 12 pieces.
a. Pro tip: Cut your rolled dough in half, then cut each half section five times for one dozen cinnamon rolls. If you wish, you can trim the ends off slightly so each roll is clean-cut.
Arrange the rolls in the greased cast iron skillet or 9x13 baking dishg dish, loosely top with plastic, and let rise for about 30 minutes.
Preheat the oven to 375 degrees while the dough is rising.
Bake for 30-35 minutes until they are lightly browned on top.
Cream Cheese Frosting
While baking, mix the icing by placing the butter and cream cheese in a bowl and mix with an electric mixer (stand or hand held) until creamy, about 2 minutes. Mix in the lemon juice and zest. Then, slowly add the powdered sugar ½ cup at a time until smooth and fluffy.
Let the sweet rolls cool for 10 minutes, then spread icing over the rolls and serve warm.
Notes
This dish can also be baked in a round cast-iron skillet of 12 inches or larger, if desired. Cast iron retains more heat so double-check the rolls halfway through the baking process to ensure they aren’t overcooked.
Leftovers can be stored in an airtight container and refrigerated up to 3 days after baking, 1-2 days at room temperature.
If you don't have a stand mixer, stir the ingredients together with a wooden spoon and knead for 5 minutes by hand.