Orly's Gluten Free Chocolate Babka

Just wanted to tell you how DELICIOUS your challah and babka were! A real treat! Great texture, not too dense and heavy like other gf products. The babka especially was exactly the taste I remembered!
— Yael R
I don’t typically like chocolate desserts because they are too sweet. This babka is like a warm hug from a teddy bear. It’s comforting like a good friend. If I start eating a gluten free diet do I get to eat more of your babka?
— David D.

Dough Starter:
3/4 cup (110g)  Manhattan Blend
3 Tbsp (20g) dry yeast
1/2  cup (110ml) warm milk (105–115°)

Dough:
1/2 scant cup (85g) sugar
2 large eggs
1 tsp vanilla
1/2 tsp salt
1/2 tsp baking powder
1 1/3 cups (220g) Manhattan Blend
7 Tbsp (100g) softened butter

Extra gluten free flour for rolling

Filling & Topping:
3/4 cup (90g) cocoa powder
1 1/2 cups (300g) sugar
7 Tbsp (100g) melted butter or oil
1 egg yolk (eggwash)
chocolate chips
cake crumbs, powdered sugar and melted chocolate (optional)

Gluten Free Chocolate Babka

Heat: Pre-heat the oven to 350°F (180°C).  Grease a rectangular loaf pan.

Mix: In the bowl of your stand mixer with the paddle attachment combine the dough starter ingredients and let sit for 10 minutes.  Mix Manhattan Blend, salt and baking powder in a separate bowl.  Add the sugar, eggs, and vanilla to the bowl and mix together on low speed for 2 minutes.  Add the flour mixture to the wet mixture and mix on medium speed until fully incorporated.  Slowly add the softened butter and mix all ingredients together until it forms a smooth shiny dough.

Filling:  Refrigerate dough until it is firm and easy to roll out.   While the dough is in the fridge, prepare the filling.  Mix together a 4:1 ratio of sugar and cocoa powder in a bowl and set aside. If you want the filling to be a richer less sweet chocolate, mix a 3:1 ratio.

Shape: Using Manhattan Blend or white rice flour, turn the dough out onto a heavily floured work surface.  Using a rolling pin, roll the dough out into a rectangle, about 2cm thickness. Brush the surface of the dough with melted butter or oil, leaving a 1/2 inch border along the top edge. Then, generously cover the surface of the dough with the cocoa/sugar mixture, leaving a 3/4 inch border along the top edge.  Beginning with the long edge nearest you, carefully roll the dough into a tight cylinder, and then twist the cylinder into a loose knot.  Transfer dough into loaf pan to rise.  
Note: You can also roll the cylinder into a snail shape, like a cinnamon bun, and place it on a flat sheet pan to rise.  

Proof and Bake: Let the babka sit in a warm area (80–100°F or 40-45°C )  for 30 minutes or until doubles in size.  Eggwash the tops and sprinkle with chocolate chips.  If you have leftover gluten free cookies or cake, grind them into crumbs and top the babka with the crumbs.  Or make your own crumb/streusel topping.   Bake at 350°F (180°C) until the outside of the babka is golden brown.  The inside should be very moist.  Finish with powdered sugar and melted chocolate drizzle.