This recipe is sponsored by Birds Eye®. Transform a humble loaf of bread into a shell filled with a delicious combination of caramelized onions, broccoli and eggs. Then top it off with tons of Gruyere and broil it until it’s melty—just like everyone’s favorite part of classic French onion soup! It’s a total showstopper and the perfect holiday breakfast for the whole family.
Place a rack in the middle of the oven and preheat to 475 degrees F.
Slice off the top one-third of the bread with a serrated knife. Hollow out the loaf by cutting a circle around the inside of the bread, leaving a 1-inch border. Pull the soft bread out with your hands, making sure to leave about 1 inch intact at the bottom of the bowl as well. Tear some of the soft insides into large rustic croutons (you’ll have about 1 1/2 cups). Reserve the remaining top and bread pieces for another use (such as breadcrumbs).
Place the bread bowl and croutons on a baking sheet. Spread 2 cups Gruyere inside the bread bowl, pressing the cheese into the sides and bottom to help it adhere. Bake until the cheese is melted and the croutons are golden, about 10 minutes. Set aside.
Cook the broccoli according to the package directions. Transfer to a colander to drain until cool, 5 minutes. Coarsely chop the broccoli and set aside.
Melt 3 tablespoons butter in a large nonstick skillet over medium heat. Add the onions, thyme, bay leaf, sugar, 1 teaspoon salt and a few grinds of pepper. Cook, stirring occasionally, until the onions are soft and golden brown, 16 to 20 minutes. (If the onions begin to darken too quickly, reduce the heat to low, add 1 teaspoon water and use a wooden spoon to scrape up any brown bits that have formed on the bottom of the pan.)
Remove and discard the thyme sprigs and bay leaf from the onions. Stir in the balsamic vinegar and cook until it is fully reduced and the pan is dry, about 2 minutes. Transfer the onions to a bowl and set aside. Rinse and wipe out the skillet.
Melt the remaining 3 tablespoons butter in the same skillet over medium heat.
Meanwhile, beat the eggs, heavy cream, 1 teaspoon salt and a few grinds of pepper in a medium bowl. Add the egg mixture to the skillet and cook, moving the eggs back and forth with a rubber spatula as they begin to set, until just cooked through and slightly creamy, 5 to 7 minutes. Remove from the heat and fold in the broccoli.
Spoon the mixture into the bread bowl, firmly pressing it down with the back of the spoon (you should have about 7 cups of filling). Top with the caramelized onions, then the croutons. Mound the remaining 3 cups Gruyere on top and bake until the cheese is melted and golden around the edges, about 20 minutes. Let cool on the baking sheet for 5 minutes before slicing into wedges.