Chocolate Babka: layers of super rich and yeasty brioche dough, layered with straight up dark chocolate. It's a major win for breakfast or as a snack with hot chocolate. It also makes an amazing Christmas neighbor gift!
To make the dough: In a glass measuring cup, warm the milk in the microwave. Be careful not to overdo it. You should be able to put your finger in with absolutely no discomfort. If you warm it too much, put it in the fridge for a while. Add 2 teaspoons of sugar and 4 teaspoons of yeast, and stir to combine. Let the mixture sit for 5-10 minutes until it is foamy. If it does not foam--and I mean at least double in size--toss it and start over.
Add the yeast mixture to a stand mixer or large bowl. Add 1/2 cup sugar and 1/2 cup of flour and stir to combine (use the paddle or a spoon, or hold the dough hook in your hand to mix it.) Add eggs, yolk, vanilla, and salt, and stir to combine. Add the 2 and 3/4 cup flour and use the dough hook to mix it up. It will be very soft.
Add the softened butter a little bit at a time, beating thoroughly each time. Once it is all mixed in, knead with the hook for about 4-5 minutes. The dough should be shiny and form strands from paddle to bowl.
Lightly oil a large bowl, and scrape the dough in. Cover with plastic wrap and let rise in a warm place for at least 1 and 1/2 to 2 hours, or until doubled in size.
Assemble babkas with the filling: Sprinkle the top of the dough with flour and punch it down with your hand. Knead by hand in the bowl, adding flour until it is workable and able to be rolled out. Divide the dough in half.
On a lightly floured silpat or heavily floured work surface, roll out 1 piece of dough into an 18- by 10-inch rectangle.
In a small bowl, beat together yolk and cream.
Spread 2 1/2 tablespoons softened butter on dough, leaving a 1/2-inch border on the edges. Brush a light amount of egg wash on the long border furthest from you.
Use a knife or food processor to finely chop 5 ounces of the chocolate, about half of a ten-ounce bag. Sprinkle half of the chopped chocolate over the dough, then sprinkle half of the whole chocolate pieces over the dough.
Sprinkle with half of the 1/3 cup of sugar; just eyeball it. Starting with the long side that is not brushed with the egg wash, roll dough into a snug log. Pinch firmly along egg-washed seam to seal. Bring ends of log together to form a ring, and pinch it to seal, using more egg wash if necessary. Twist the entire ring twice to form a double figure 8. (See photos below)
Line two 9x5 loaf pans with parchment paper. Gently place the babka into the first pan, and cover with plastic wrap that has been sprayed with nonstick spray. Let rise in a warm place for 1 and 1/2 to 2 hours. The bread needs to rise to at least the top of the pan, if not more. (Alternatively, let dough rise in pans in refrigerator 8 to 12 hours; bring to room temperature, 3 to 4 hours, before baking.)
Make another babka with the remaining piece of dough, butter, egg wash, chopped chocolate, whole chocolate, and sugar.
Chill remaining egg wash, covered, to use later.
Place oven rack in middle position and preheat oven to 350°F. Brush tops of dough liberally with remaining egg wash. Bake until tops are deep golden brown and bottoms sound hollow when tapped (when loaves are removed from pans), about 40 minutes. (If you are doing mini loaves bake for about 30-35 minutes.) Transfer loaves to a rack and cool to room temperature.
Source: adapted from Buttered Up , originally from Epicurious