Step 1: In a small bowl, combine warm milk and 1 tablespoon of the granulated sugar. Sprinkle the active dry yeast over the top and let sit for 5-10 minutes until foamy.
Step 2: In the bowl of a stand mixer, combine the flour, remaining granulated sugar, and salt. Make a well in the center.
Step 3: Pour the yeast mixture into the well. Add the 2 eggs and softened butter cubes. Using the dough hook attachment, knead on low speed for 8-10 minutes until the dough is smooth, elastic, and pulls away from the sides of the bowl. It will be soft and slightly sticky.
Step 4: Transfer the dough to a lightly oiled bowl, turning once to coat. Cover with plastic wrap and let rise in a warm place for 1.5-2 hours, or until doubled in size.
Step 5: While the dough rises, prepare the filling. In a medium bowl, combine the diced ham, chopped spinach, softened cream cheese, garlic powder, black pepper, and salt. Mix until well combined.
Step 6: Once the dough has risen, gently punch it down. On a lightly floured surface, roll the dough into a large rectangle, approximately 18×12 inches (45×30 cm).
Step 7: Spread the savory filling evenly over the rolled-out dough, leaving a 1-inch border on one long edge. Place the round of Camembert cheese in the center of a baking sheet lined with parchment paper.
Step 8: Carefully lift the dough and wrap it around the Camembert, enclosing the cheese within the dough rectangle. Bring the long, unfilled edge over to meet the other long edge, pinching to seal, creating a long filled log.
Step 9: Using a sharp knife or pizza cutter, cut the dough log lengthwise into 1-inch wide strips, starting from the center and working outwards (you’ll have two long, filled strips). Leave about 1-2 inches of dough intact where they meet at the base of the Camembert.
Step 10: Carefully twist each strip a few times, then arrange them around the Camembert to form a wreath, pinching the ends together to connect. Ensure the Camembert is nestled in the center.
Step 11: Cover the shaped brioche wreath loosely with plastic wrap and let it rise again for 30-45 minutes, or until visibly puffy.
Step 12: Preheat your oven to 375°F (190°C). In a small bowl, whisk the remaining egg with 1 tablespoon of water for the egg wash.
Step 13: Brush the brioche wreath generously with the egg wash. Drizzle the top of the Camembert with olive oil and sprinkle with chopped fresh rosemary.
Step 14: Bake for 30-35 minutes, or until the brioche is golden brown and cooked through. If the brioche browns too quickly, tent loosely with foil.
Step 15: Let cool for a few minutes before serving warm, allowing guests to pull apart the brioche to dip into the molten Camembert.