In a large bowl or bowl of a stand mixer, combine flour, sugar, yeast, salt, and cinnamon. Add butter and warm eggnog. Stir until combined.

Transfer dough to a lightly floured surface and knead 10 minutes, adding more flour as needed until a smooth, elastic and only slightly sticky dough forms OR using dough hook attachment, knead dough in stand mixer on medium speed 5 minutes, adding more flour as needed until a smooth, elastic and only slightly sticky dough forms.

Shape dough into a ball and place in a lightly greased bowl. Cover with plastic wrap and let rise in a warm place 1 1/2 to 2 hours until nearly doubled.

Punch down dough. On a lightly floured surface, roll out dough into a 16-by-8-inch rectangle. Brush with egg wash, then reserve egg wash for later. In a small bowl, combine brown sugar, flour and cinnamon; sprinkle evenly over dough.

Starting from one short end, tightly roll up the dough into a log. Pinch seam to seal. Place dough seam-side down in a lightly greased 8 1/2-by-4 1/2-inch loaf pan (a 9-by-5-inch loaf pan also works). Cover with lightly greased plastic wrap and let rise 1 hour in a warm place until the dough comes about 1 inch over the top of the pan.

Heat oven to 350 degrees F. In a small bowl, combine flour, sugar and cinnamon. Cut in butter with a pastry blender or your fingers until mixture resembles coarse crumbs. Brush top of loaf with reserved egg wash. Carefully sprinkle and pat streusel mixture on top of dough, being careful not to deflate dough.

Bake loaf 45 to 50 minutes until golden brown. Tent with foil halfway through if top of loaf gets brown too quickly. Cool loaf 5 minutes in pan, then carefully remove and transfer to a cooling rack to cool completely.

In a small bowl, combine powdered sugar and eggnog to make a glaze. Drizzle glaze over fully cooled bread. Let set before slicing.