This recipe comes to us from Martha Stewart Living Television senior producer Caroline Kelly; it was passed down to her from her great-great-grandmother Lucille.
In a medium saucepan, combine milk, 1/2 cup sugar, butter, and salt over medium-low heat. Bring just to a simmer, then remove from heat. Let stand until cool.
Meanwhile, combine yeast, water, and a pinch of sugar in a small bowl. Let stand until foamy, about 5 minutes. Add yeast mixture and eggs to milk mixture, stirring to combine.
Butter a large bowl; set aside. Place 6 cups flour in a large bowl. Slowly stir in the milk mixture. Add enough of the remaining 2 cups flour to create a dough that comes together around the spoon, being sure not to add more than 8 cups. Transfer to a lightly floured work surface and knead until smooth and elastic, about 5 minutes. Transfer to prepared bowl, cover with plastic wrap, and let stand in a warm place until doubled in bulk, about 1 hour.
Turn dough out onto a lightly floured surface and knead until smooth, about 15 minutes. Cut into 4 equal pieces. Place on a baking sheet, cover with plastic wrap, and let stand until doubled in bulk, about 1 hour.
Preheat oven to 375 degrees. Prepare the filling: Brush 2 baking sheets with butter; set aside. Combine granulated sugar and cinnamon in a small bowl; set aside.
Roll each piece of dough into a rectangle about 12 inches wide and 17 inches long. Brush each rectangle generously with butter. Sprinkle each rectangle evenly with 2 tablespoons cinnamon sugar mixture, 2 cups brown sugar, and 1 cup fruit or nuts. Roll up from long side like a jelly roll. Place 2 rolls on each baking sheet. Cut diagonal slits into the tops of rolls about 1 inch apart. Brush rolls with remaining butter. Sprinkle each roll with 2 tablespoons cinnamon sugar and 1/2 cup dried fruit or chopped nuts, pressing into slits.
Let stand for 15 minutes. Transfer to oven and bake for 15 minutes. Reduce oven to 350 degrees.and continue to bake until light golden brown, about 20 minutes more. Transfer baking pans to wire racks and let cakes cool briefly.
Prepare the icing: In a medium bowl, combine confectioners' sugar and water, stirring to make a smooth glaze. Drizzle generously over warm coffee cakes.