Chocolate Babka

Ingredients

• ½ cup/118 milliliters whole milk
• 1 package (1/4 ounce/7 grams) active dry yeast
• ⅓ cup/67 grams granulated sugar, plus a pinch
• 4 ¼ cups/531 grams bread flour, more as needed
• 1 ½ teaspoons fine sea salt
• 1 teaspoon vanilla extract
• 1 teaspoon grated lemon zest (optional)
• ½ teaspoon freshly grated nutmeg
• 4 large eggs lightly beaten
• 10 tablespoons/140 grams unsalted butter, at room temperature, plus more for greasing bowls and pans
• FOR THE FUDGE FILLING: · ½ cup/100 grams granulated sugar
• · ¾ cup/177 milliliters heavy cream or half-and-half
• · Pinch kosher salt
• · 6 ounces/170 grams extra bittersweet chocolate, preferably between 66 and 74 percent cocoa, coarsely chopped.
• o Last time I made this I used 4 oz of Ghirardelli Bittersweet 60% cocoa and 2 oz Theo Pure 85% Dark Chocolate (based on hitting two supermarkets ☹) It worked well
• · 8 tablespoons/112 grams/1 stick unsalted butter, diced, at room temperature
• · 2 teaspoons/10 milliliters vanilla extract
• FOR THE CHOCOLATE STREUSEL: · ½ cup/60 grams all-purpose flour
• · 3 tablespoons/45 grams granulated sugar
• · 1 ½ tablespoons/11 grams cocoa powder
• · ½ teaspoon kosher salt
• · 4 ½ tablespoons/64 grams unsalted butter, melted
• · ⅓ cup/60 grams semisweet chocolate chips
• FOR THE SYRUP: · ⅔ cup/135 grams granulated sugar
• · ⅔ cup/158 milliliters water