6 - 6 1/2cupsflour, divided, plus more for work surface
8tablespoonssugar, divided
1 1/2teaspoonssalt
2cupsmilk
1/2cupshortening
1package active dry yeast
1/4cupwarm water (about 105◦)
Filling
2tablespoonsmilk
6tablespoonssugar
2teaspoonscinnamon
1 1/4cupsraisins (preferably muscat)
4tablespoonsbutter, cut into small pieces
Icing
2tablespoonsbutter, softened
1teaspoonvanilla
4cupsconfectioner's sugar
6tablespoons(or more) milk
Instructions
In a large bowl, stir together 5 1/2 cups of flour, the salt, and 6 tablespoons of the sugar.
Scald the milk by heating it in a small pan over medium-low heat. Stir constantly until the milk starts to steam and small bubbles appear at the edges - do not let it come to a boil. Remove from heat immediately and add the shortening. Let the mixture cool until just warm, about 105◦.
In a small bowl, combine yeast with the remaining 2 tablespoons sugar. Add warm water and let stand for 10 minutes.
Add the yeast and milk mixtures to the flour mixture and stir until everything is fully combined.
Turn dough out onto a lightly floured work surface. Sprinkle an additional 1/2 cup of flour on the dough and knead until smooth, adding up to 1/2 cup more flour if it's still sticky. Place dough in a greased bowl, cover with a damp towel, and let rise in a warm place until doubled in size, about an hour.
Place dough on freshly floured work surface and roll into a 1/4-inch thick rectangle, approximately 17 x 24-inches. Drizzle with the milk, spreading it into a thin layer with your fingers. Sprinkle on the sugar and cinnamon, evenly distribute the raisins, then dot with the butter.
Roll up dough from the long edge and pinch the seam firmly together. (If it's not sticking, rub the inside of the seam with a little more milk and try again.) Squish the dough from the center out to make it a more even roll - it should be 1 1/2 - 2 inches in diameter. Cut the roll into 24 slices, discarding both ends, and place slices cut side down in two greased 8 x 11-inch baking dishes.
Cover the pans and let the rolls rise again for an hour, preheating your oven to 425◦ towards the end. Bake rolls until the tops are golden, about 20 minutes.
For the icing, using an electric mixer, beat the butter and vanilla until light and fluffy. Add the sugar 1 cup at a time, beating thoroughly after each addition. Add the milk and beat again, adding more milk by the teaspoonful if needed, until you reach frosting consistency.
Frost the rolls with the icing once they have cooled.