Step 1

Preheat the oven to 350°F. Unwrap one stick of butter and set on a plate near the oven to come to room temperature. Cut the second stick into cubes and freeze for 10 minutes.

Step 2

In a large bowl, whisk together the flour, 2 tablespoons of the sugar, baking powder, salt, and baking soda. Add the chilled butter and toss to coat.

Step 3

Using your fingers, pinch the butter into the flour until it resembles coarse meal. Add buttermilk and stir until no dry flour remains.

Step 4

Turn out dough onto a flour-dusted surface. Dust the top of the dough with flour and roll out into a 12x18-inch rectangle.

Step 5

Carefully spread soft stick of butter over the top of the dough and sprinkle with remaining sugar and cinnamon.

Step 6

Starting at a long end, roll the dough up jelly-roll style and slice into 12 even slices.

Step 7

Place rolls in a 9x13-inch baking dish and set in the refrigerator to chill while you make the sauce:

Step 8

In a medium saucepan, combine the condensed milk, milk, powdered sugar, butter, and salt over medium-high heat.Stir gently until mixture starts to bubble and sugar has dissolved.

Step 9

Remove from heat and stir in vanilla extract.

Step 10

Pour over rolls; they'll float but that's okay. Bake until puffy and golden brown, 40-45 minutes. Let sit 5 minutes before serving. Drizzle with sauce and enjoy!