• In a large mixing bowl, combine yeast and warm water. Let the mixture stand until it is foamy or creamy, about 5 minutes. Add milk, eggs. canola oil, brown sugar and salt. Stir everything well.
• Add 2 cups of whole wheat flour and stir it in using a large metal spoon until the flour is incorporated. Add the remaining 2 cups of whole wheat flour, one cup at a time, stirring well after each addition. The mixture is now a sticky, shaggy mass.
• Sprinkle just a little amount of the all-purpose flour ( about a tablespoon or so), once or twice over the dough, and stir until the dough has gathered in the center of the bowl.
• Generously flour a working surface with the all-purpose flour. Scrape the dough from the bowl and into the board. Dust your hands with all-purpose flour. Knead for about ten minutes, until the dough is elastic and smooth. During kneading, you will need to dust your board around the area where it sticks, and your hands as well. However, only dust with flour as needed. With whole wheat dough, the stickiness does not totally go away so flour only just until the dough is manageable enough and don't attempt to dump the flour in there. It will dry up the dough. You may not need the entire amount of all-purpose flour.
• A quick windowpane test will tell you if you have kneaded enough. Shape the dough into a ball and place it in a lightly oiled bowl. Cover with a kitchen towel and let it rise for 1 and 1/2 hour, or until it is doubled in size.
• Punch the dough down and roll it into a rectangle that is 12x16 inches. Trim the sides if you like. To fill the dough, spread 3 tbsp melted butter all over the rectangle. Combine the cinnamon and sugar and sprinkle it on the dough. 
• Roll the dough into a tight log by starting on the short edge of the rectangle. Cut the log into 1 inch thick rounds. You will get about 12-14 discs. Arrange the rounds in 2 greased 9-inch round pans or a 9x13 baking pan. To let them rise, turn on the oven to 200 F. Once it has reached that temperature, turn the oven off. Place the rolls inside and let them rise for about 25 minutes. Take them out and preheat oven to 350 F.  Bake the rolls for 15-18 minutes, or until lightly browned. 

Make the Caramel Glaze

• In a medium saucepan bring the brown sugar and water to boil. Let it simmer until the sugar is dissolved and the mixture has thickened slightly. Stir in butter until melted. Stir in the vanilla extract. Drizzle over the buns.