Chocolate Swirl Brioche

   Makes 1 loaf

• 1/4 cup plus 1/2 teaspoon sugar, divided
• 1 packet (1/4 ounce) active dry yeast
• 2 tablespoons warm water
• 2 1/2 cups all-purpose flour, plus an additional 1/2 cup as needed
• 1 teaspoon salt
• 5 eggs, divided
• 1/2 cup (1 stick) butter, softened
• 10 ounces dark chocolate, chopped

1. In a small bowl, whisk together 1/2 teaspoon sugar, yeast, and warm water. Let sit until frothy, about 5 minutes.
2. In a stand mixer fitted with the paddle attachment, or in a large bowl, whisk together the flour, remaining 1/4 cup sugar, and salt.
3. Add the yeast mixture and stir well to combine.
4. Whisk together four of the eggs, and add slowly to the flour mixture, mixing until mostly combined (don't worry about a few dry spots here and there).
5. With the mixer running (or constantly stirring well if you aren't using a mixer), add the softened butter about a tablespoon at a time. Once the butter is well incorporated into the dough, switch to the dough hook attachment (or start kneading with your hands).
6. Knead the dough with the dough hook or your hands for 8 to 10 minutes. The dough will be quite sticky, but if it is TOO sticky, add up to 1/2 cup of flour (or even 3/4 cup if you really need it) until the dough is smooth and elastic. It should be sticky but more tacky than gooey.
7. Transfer your dough to a large greased bowl. Cover with plastic wrap or a damp tea towel and let rise in a warm spot for about 1 1/2 hours. The dough should be almost doubled in size.
8. When the dough has risen, turn it out onto a work surface. The dough is buttery enough that you shouldn't need to flour your surface. Roll the dough out to an 8- by 14-inch rectangle.
9. Spread the chopped dark chocolate evenly across the surface of the dough. Starting at a short (8-inch) end, roll the dough up into a log.
10. Grease an 8- by 4 1/2-inch loaf pan and transfer the dough, seam side down, to the pan. Cover with plastic wrap or a damp tea towel and let rise for another hour. The dough should just about reach the top of the pan at this point.
11. When the hour is almost up, preheat the oven to 375° F.
12. Once the dough is ready, beat the remaining egg. Brush the egg lightly over the surface of the dough.
13. Bake the loaf for 30 to 40 minutes. The top should be a deep, dark golden brown and sound hollow when you tap it.
14. Remove the loaf from the oven, let it cool for a few minutes, then turn it out onto a rack to finish cooling. Wait for the loaf to cool entirely before slicing! (Unless you want warm bread...which I always do...just know that if you slice into it while the loaf is still hot, it will be a little messy-looking from the molten chocolate).