Prepare the bacon jam. Heat medium pot to medium high. Add bacon and cook until crisp for 7-8 minutes. Remove bacon from pot with slotted spoon;drain on plate lined with paper towels.
Pour off most of bacon fat (to reserve for other uses, if desired). Leave about 1 tablespoon of fat in pot. Add onion and sweat until translucent and tender, about 4-5 minutes.
Stir in reserved bacon, brown sugar, and vinegar. Bring mixture to a simmer over medium low heat.
Simmer until mixture thickens slightly, about 8-10 minutes. Remove from heat; purée jam using an immersion blender or food processor – jam should be thickened, but coarse. Stir in sage, thyme, and black pepper. Set aside.
Prepare bread dough. Place flour, salt and yeast in bowl of electric mixer fitted with the dough hook attachment and mix flour, salt, and yeast to combine.
In a small pot, heat milk and brown sugar until warm (approx. 95°F), for about 1 minute.
Pour warm milk mixture into the mixer bowl and begin to mix on low speed. Add eggs and mix until mixture forms a ball around the dough hook, about 3 minutes. Increase speed to medium and mix until dough is smooth, about 3 minutes.
Transfer dough to buttered medium bowl and cover with plastic wrap. Let rise until nearly double in size, 1 – 1 1/2 hours.
Lightly butter 12 x 4 inch (or 9 x 5-inch) loaf pan. On lightly floured surface, roll dough into 12 x 12-inch square. Cut dough vertically into four 3-inch strips. Then, cut strips horizontally across to form squares for a total of 16 dough squares.
Assemble the loaf. Scoop 1 tablespoon bacon jam into center of each piece of dough; top with 2 heaping tablespoons of shredded Emmi Kaltbach™ Le Gruyère® AOP Cheese. Fold dough squares in half, pressing to distribute filling evenly inside. Repeat with the remaining pieces of dough.
Place each square (rounded side down) in prepared loaf pan, stacking filled pieces of dough vertically like books on a bookshelf.
Cover pan with buttered plastic wrap and let rise 30-45 minutes. Meanwhile, heat oven to 350°F.
Brush loaf with about half the melted butter and bake until the bread begins to turn golden brown, about 20-25 minutes. Brush loaf with butter again and bake until deeply golden brown, with the internal temperature reaching 195°F.
Let cool 15 minutes inside the loaf pan, then turn out onto cooling rack to cool completely before serving.