Spray a 9 by 13 inch pan well with bakers spray. Preheat oven to 350
Combine 4 cups flour, baking soda, baking powder and salt in a bowl and whisk to combine, set aside
In a small bowl combinebrown sugar and cinnamon, set aside
In a saucepan, whisk milk, sugar and butter and heat just until it reaches a simmer, don't allow to boil. Remove from heat and transfer to a large bowl and add vanilla extract and stir in. Cool to 95 to 100F
Add yeast to warm milk and whisk in
Add flour mixture to yeast mixture to combine completely the dough will be soft, cover with plastic wrap and let rise 1 hour or until doubled in size
Turn dough out on to a floured surface and knead in remaining 1/2 cup flour to make a soft dough. Add more flour if dogh is very sticky but only if needed, its should be a very soft dough for a tender roll.
Roll into a 18 by 9 inch rectangle
Spread with melted butter thinly covering
Sprinkle with brown sugar and cinnamon.
Sprinkle with raisins
Roll up tightly, pinching closed
With a very sharp knife cut in 2 1/2 inc slices
Place in prepared pan, almost touching. Cover with towel and let rise about 20 to 35 minutes until doubled in size
Brush lightly on tops with remaining melted butter
Bake about 25 to 30 miinutes, until golden and middle roll is cooked through with no raw dough. Slide a thin knife to check if your not sure. Remove and cool only 4 to 5 minutes before icing
Make icing
Beat butter and mascarpone cheese until smooth
Beat in confectioner's sugar and vanilla until smooth
Spread over warm cinnamon rolls
