NOTE: The amount of flour can vary from 2 1/4 to 2 3/4 cups
Stir 1 3/4 cups of the whole wheat flour, sugar, undissolved yeast, salt and cinnamon together in a large mixing bowl. Heat the water and butter in a saucepan over low heat to very warm (120-130 degrees F.). Remove from the heat and stir in the buttermilk. Add to the flour-yeast mixture and beat, with an electric mixer on medium speed, until smooth, about 2 minutes. Add the eggs and beat an additional 2 minutes, then stir in the raisins. Gradually add the remaining 1/4 cup of whole wheat flour and enough white flour to make a stiff but light dough. (Heaviness indicates too much flour and the bread will not rise correctly.) Let rest for 5 minutes.
Turn the dough out onto a lightly floured surface and knead until smooth, about 5 to 8 minutes. Cover with the mixing bowl and let rest for 30 minutes. Punch the dough down and divide in half. Let rest 10 minutes, then roll each half to a 12 X 7-inch rectangle. Beginning at the 7-inch side, roll up tightly like a jelly roll and seal the edges. Tuck the ends under to form rounded edges, (the loaf should be about 7 X 3-inches in size). Place on a greased baking sheet. Brush with oil and repeat for the second batch of dough. Cover and let rise in a warm place until almost doubled, about 30 minutes. Bake in a preheated 375 degree F. oven for 25 minutes or until the loaves sound hollow when tapped. Remove from the baking sheet and cool on wire racks for 20 minutes. Frost with the vanilla icing if desired.
VANILLA ICING: Combine the sugar, vanilla, and milk in a bowl and beat until smooth.