In a bowl, mix 2 cups flour, yeast, sugar, and salt.
Warm milk and butter until just warm. Add to dry ingredients.
Add egg and mix well. Gradually add remaining flour until a soft dough forms.
Knead 8–10 minutes until smooth and elastic.
Place in an oiled bowl, cover, and rise 1 hour until doubled.
Roll dough into a large rectangle. Spread butter, sprinkle brown sugar and cinnamon.
Roll tightly and cut into 12 rolls. Place in a lined 9×13 pan.
Cover and rise 1 hour until puffy.
Bake at 350°F (175°C) for 30 minutes until golden.
Whisk all tres leches ingredients. Pour over warm rolls. Rest 15 minutes.
Beat frosting ingredients until fluffy. Spread over rolls.
Serve warm and enjoy