Step 1

Pour warm milk into a small bowl. Sprinkle yeast and pinch of sugar over milk, stir lightly; let stand until foamy, about 5 minutes.

Step 2

In a bowl of electric mixer with paddle attachment, mix together ¾ cup sugar, 2 eggs, vanilla and egg yolks. Add yeast mixture and lightly mix to combine.

Step 3

In a bowl combine flour and salt. Add to egg mixture, and beat on low speed until almost all the flour is incorporated, about 30 seconds. Change to the dough hook. Add 2 sticks butter, and beat until flour mixture and butter are completely incorporated, and a smooth, soft dough that’s slightly sticky when squeezed is formed, about 10 minutes.

Step 4

Turn dough out onto a lightly floured surface, and knead a few turns until smooth. Butter a large bowl.

Step 5

Place dough in bowl, and turn to coat. Cover tightly with plastic wrap. Set aside in a warm place to rise until doubled in bulk, about 1 hour.

Step 6

To make the filling: Place chocolate chips, ½ cup sugar. ½ cup raw sugar, walnuts and cinnamon in the bowl of a food processor, process into coarse crumbs.

Step 7

Add the 1 ½ sticks butter and process until well combined; set filling aside.

Step 8

To make the streusel topping: In a large bowl, combine sugar, flour, and butter. Using a fork, stir until fully combined with clumps ranging in size from crumbs to 1 inch.

Step 9

To assemble: Preheat oven to 350°F. Generously butter your 9-by-5-by-2 3/4-inch loaf pan.

Step 10

In a small bowl beat the remaining egg with the 1 Tbsp cream, set bowl aside

Step 11

Punch back the dough, and transfer to a clean surface. Let rest 5 minutes. Cut into three equal pieces. Keep two pieces covered with plastic wrap while working with the remaining piece. On a generously floured surface, roll dough out into a 16-inch square; it should be about 1/8-inch thick.

Step 12

Brush edges with egg wash. Crumble ⅓ of the chocolate filling evenly over dough, leaving a 1/4-inch border. Roll dough up tightly like a jelly roll. Pinch ends together to seal. Now, twist 5 or 6 turns.

Step 13

Fold long roll in ½ and brush top of roll with egg wash. Carefully crumble 2 Tbsp more filling over the roll and twist folded roll a few more times.

Step 14

Place twisted roll into prepared baking pan (it will be a little messy)

Step 15

Brush the top of babka with egg wash. Crumble ⅓ of streusel topping over each loaf. Loosely cover each pan with plastic wrap, and let stand in a warm place 20-30 minutes.

Step 16

Bake babkas, rotating halfway through, until golden, about 35 minutes test for doneness. Toothpick should come out clean of dough when done. Remove from oven and transfer to wire racks until cool. Remove from pans; serve.