Combine the water, honey, butter and salt together in a small bowl, stir to combine and set aside to cool completely. Whisk in the egg once cooled.

Combine the water and sugar in a glass measuring cup or small bowl and sprinkle with the yeast.

In a large bowl, combine the cooled mixture from Step 1 along with the yeast mixture from Step 2 and stir in the whole wheat flour.

Gradually add the remaining all-purpose flour until the dough gets too difficult to stir in the bowl.  Transfer the dough to a clean floured surface and knead by hand until the dough is smooth and elastic, about 10 minutes, adding more all purpose flour as needed.  

Place the dough in a large greased bowl, cover with a clean dish towel, and place in a draft-free warm area to rise until doubled, about 1 hour. Punch down the dough once and repeat.

Grease a 9x13" baking dish. On a lightly floured surface (use all-purpose flour for this), roll out your dough to form a rectangle, approximately 12" x 24".  Again, it doesn't have to be exact!

For the filling: spread the butter evenly on the dough to cover and sprinkle with the brown sugar and cinnamon to evenly coat the dough. Top with an even layer of the shredded apple and raisins if using, and drizzle with honey.  Roll the dough into a long log from the longest edge of your rectangle until it is completely and tightly rolled. Using a sharp knife, cut the roll into 12 even rolls.  Place the rolls cut side up evenly in the pan as pictured, cover with a clean towel, and allow them to rise in a slightly warm and draft-free area until they are doubled in size.

Preheat the oven to 350 F. Once doubled, bake for 15-20 minutes or until nicely browned.  Immediately turn the pan over onto a sheet of parchment paper on the counter once you remove them from the oven if not glazing; otherwise keep the buns in the pan and glaze. Make the glaze by whisking together the icing sugar, vanilla and milk, one teaspoon at a time, until the glaze is a thick but "drizzable" consistency.