In a large mixing bowl, stir 1 teaspoon of sugar and yeast into 1 cup of warm water (110 degrees).

Let the yeast mixture stand for 2-3 minutes until foamy.

Add 1/2 cup of sugar, 2 eggs, vanilla extract, salt, 1/4 teaspoon of cinnamon, and oil to the yeast mixture.

Whisk all the ingredients together.

In a separate bowl, whisk together bread flour and all-purpose flour.

Gradually add the flour mixture to the egg/yeast mixture while mixing until a stiff dough forms.

Knead the dough on a lightly floured surface for 8-10 minutes, adding more flour as needed to form a smooth dough.

Place the dough in a lightly greased bowl, cover with a towel, and set in a warm place.

Let the dough rise for 45 minutes to 1 hour, or until it doubles in size.

While the dough is rising, place the diced apples in a bowl and toss with the remaining 1/2 cup sugar and 1 teaspoon of cinnamon.

Prepare the egg wash by whisking together the remaining egg yolk with a tablespoon of water.

Spray a 12x5 inch loaf pan generously with nonstick cooking spray.

If a large pan is not available, use two 9x5 inch loaf pans.

Turn the risen dough onto a lightly floured surface.

Roll out or pat the dough into a large round, about 10 inches across.

Press half of the apple mixture into the dough.

Fold the outer edges or corners of the dough over the apples and press to seal.

Flatten the dough slightly and press in the remaining apples, folding the dough over the apples and pressing them in place.

Rest the dough for 5 minutes on the counter.

Using a sharp knife, cut the dough into approximately 16 uneven chunks.

Lay the pieces of apple-filled dough in the prepared loaf pan, lining the bottom first.

Gently lay the remaining pieces on top, mixing the angles of the cut chunks.

Top with any escaped apple pieces.

Spray the top of the dough with a light coating of nonstick cooking spray.

Place the pan(s) in a large plastic bag and seal loosely, or cover with a towel.

Set in a warm place for 45-90 minutes, until the dough is almost flush with the top of the pans.

Preheat the oven to 350 degrees Fahrenheit.

Remove the pans from the bag and dab the egg wash thoroughly and generously over the dough.

Since the dough surface is not smooth, you may have to drizzle the egg wash and then dab it.

Sprinkle the top of the dough with coarse sugar.

Bake at 350 degrees Fahrenheit for 50-55 minutes, or until well browned.

Cool in the pan for 10 minutes before removing and cooling on a wire rack.

Pull apart or slice to serve.