To Make the Brown Butter:

• Cube the butter and place in a light-colored skillet. (Light colored helps you determine when the butter begins browning.) Melt the butter over medium heat, stirring constantly.
  345 g unsalted butter*
• Once melted, the butter will begin to foam. Keep stirring. After 5-8 minutes, the butter will begin browning; you’ll notice lightly browned specks begin to form at the bottom of the pan and you'll begin to smell a nutty aroma. Once browned, immediately remove from heat, pour into a heat-proof bowl, and freeze until solidified, about 20 minutes.

To Make the Brioche Dough:

• In the bowl of a stand mixer or in a large mixing bowl, combine 4 cups (500g) of the flour, Fleischmann’s® RapidRise® Instant Yeast, sugar, and salt. Add the milk, brown butter, eggs, and vanilla bean paste and mix until the ingredients are just barely combined and a shaggy dough forms.
  500-560 g all-purpose flour, 7 g Fleischmann’s® RapidRise® Instant Yeast, 100 g granulated sugar, 1 tsp fine sea salt, 240 g milk, 85 g brown butter, 2 large eggs, seeds scraped from 1 vanilla bean or 1 tsp vanilla bean paste
• Add the remaining ¼ cup (60g) of flour and, using the hook attachment, beat on low speed until a soft dough forms. Increase the speed to medium and beat until the dough is soft and supple, about 6 minutes longer. *If you do not have a stand mixer with a hook attachment, knead the dough by hand in this step for 8-10 minutes.*
• Transfer the dough to a lightly floured surface and knead it with your hands for 1 minute. Form the dough into a ball and transfer it to a lightly greased bowl. Cover the dough loosely with plastic wrap and let rest for 15 minutes. Prepare the filling while the dough rests.

To Make the Brown Butter Cinnamon Sugar Filling and Assemble:

• Add the brown butter, dark brown sugar, and cinnamon to a medium bowl and combine using a fork until a thick paste forms. Set aside until needed.
  120 g brown butter, 220 g dark brown sugar, 12 g ground cinnamon
• Grease the bottom and sides of a 13 x 9-inch baking dish and set aside. Turn the risen dough out onto a lightly floured work surface, punch it down and, using a rolling pin, roll into a 14×20-inch rectangle. Make sure the dough is smooth and evenly thick.

• Spread the brown butter cinnamon sugar filling all over the dough. Tightly roll up the dough to form a 20-inch-long log and cut into 12 even rolls. Arrange them in the prepared baking pan. Cover the pan and allow the rolls to rise for 50-60 minutes or until nearly doubled in size.
• While the rolls are rising, preheat the oven to 350°F (180°C).
• Bake the rolls for 20-25 minutes, until the rolls are golden brown. While the rolls are baking, make the icing.

To Make the Brown Butter Cream Cheese Icing:

• In a medium bowl, whisk together the cream cheese and brown butter until combined. Add the powdered sugar, vanilla bean paste, and milk and whisk until smooth and combined. If the icing is too thin, add a little more powdered sugar; if it's too thick, add more milk.
  55 g cream cheese, 45 g brown butter, 120 g powdered sugar, ½ tsp vanilla bean paste, 30 g milk
• Drizzle the icing over the warm cinnamon rolls once you remove them from the oven. Cover leftover frosted or unfrosted rolls tightly and store at room temperature for up to 3 days.