Instructions

For the yeast coffee cake dough:

1. In a large mixing bowl, combine ¾ cups  of the flour, the sugar, salt and yeast. 
2. In a saucepan, combine the milk, water and butter and heat over medium heat until warm and the butter is just melted. 
3. With an electric mixer on low speed, gradually add the warm liquid to the flour/yeast mixture, beating until well blended. Increase mixer speed to medium and beat 2 minutes. Add the eggs and ½ cup flour and beat for 2 more minutes.
4. Using a wooden spoon, stir in enough of the remaining flour to make a dough that holds together. Turn out onto a floured surface (use any of the ¾ cups of flour remaining) and knead the dough for 8 to 10 minutes until the dough is soft, smooth, and elastic, keeping the work surface floured and adding extra flour as needed. Alternatively, you can use a dough hook in an electric mixer. I actually did some of both.
5. Place the dough in a lightly greased bowl, turning to coat all sides. Cover the bowl with plastic wrap and a kitchen towel and let rise until double in bulk, 45 – 60 minutes. The rising time will depend on the type of yeast you use.

For the filling:

1. In a small bowl, combine the cinnamon and sugar for the filling if using. Mix together the nuts and chocolate.

For the meringue:

1. Once the dough has doubled, make the meringue: In a clean mixing bowl – ideally a plastic or metal bowl so the egg whites adhere to the side (they slip on glass) and you don’t end up with liquid remaining in the bottom – beat the egg whites with the salt, first on low speed for 30 seconds, then increase to high and continue beating until foamy and opaque. 
2. Add the vanilla then start adding the ¼ cup sugar, a tablespoon at a time as you beat, until very stiff, glossy peaks form.

Assembly of Coffee Cake:

Prepare an egg wash by beating 1 egg

1. Line 2 baking/cookie sheets with parchment paper. Punch down the dough and divide in half. On a lightly floured surface, working one piece of the dough at a time (keep the other half of the dough wrapped in plastic), roll out the dough into a 20 x 10-inch (about 51 x 25 ½ cm) rectangle. 
2. Spread the meringue evenly over the rectangle up to about ½-inch (¾ cm) from the edges. (I did not use quite all of it) Sprinkle half of your filling evenly over the meringue
3. Now, roll up the dough jellyroll style, from the long side. Pinch the seam closed to seal. Very carefully transfer the filled log to one of the lined cookie sheets, seam side down. Bring the ends of the log around and seal the ends together, forming a ring, tucking one end into the other and pinching to seal.
4. Using kitchen scissors or a sharp knife (although scissors are easier), make cuts along the outside edge at 1-inch (2 ½ cm) intervals. Make them as shallow or as deep as desired but don’t be afraid to cut deep into the ring. Cover the  coffee cake with plastic wrap and allow it to rise again for 45 to 60 minutes.
5. Preheat the oven to 350°F (180°C). Brush the tops of the coffee cakes with the egg wash. Bake in the preheated oven for 25 to 30 minutes until risen and golden brown. The dough should sound hollow when tapped. Dust with confectioners sugar when cooled. Enjoy!