I met Rick Browne, master barbecuer and cookbook author, and his wife when they were dining at Mother’s Bistro. Father’s Day was approaching and I wanted to honor a father that month, so I asked Rick. His wife brought me his cookbooks and we put together a menu that included this dish. Ironically, it came from his mother.
Think of this dish as a blank slate. Consider the flavors of what you’re planning to serve it with and add a little of that flavor to the mix, things like fresh thyme or rosemary; bacon crumbles or roasted garlic; goat cheese, Gruyere, Cheddar, or blue cheese.
4 tablespoons (1/2 stick) unsalted butter (divided), plus more for greasing the dish
2 tablespoons olive oil (divided)
4 large yellow onions, thinly sliced (8 cups)
2 1/2 teaspoons kosher salt (divided)
1/2 teaspoon freshly ground black pepper (divided)
1/4 cup dry vermouth
1 clove garlic, minced
4 heaping cups French bread cut into 2-inch squares (6 to 7 ounces) preferably a day or two old
3 large eggs
2 cups half-and-half
2 cups (about 8 ounces) shredded Swiss or Emmentaler cheese
Butter the inside of a 13x9x2-inch baking dish.
Heat a large (12- to 14-inch) saute pan over medium-high heat for a couple of minutes. When hot, add 2 tablespoons of the butter, 1 tablespoon of the oil, half of the onions at the same time. Season with 1/2 teaspoon salt and 1/8 teaspoon black pepper. Saute over high heat until the onions start to color around the edges, about 5 minutes. Lower the heat to medium and saute for 20 minutes, or until the onions are soft and lightly caramelized. Transfer the cooked onions to a baking sheet and cook the second half of the sliced onions like the first, making sure the pan is hot before adding the butter, oil, and onions and seasoning with salt and pepper.
When the second batch of onions is caramelized, add the first batch back to the onions in the pan. Add the vermouth and deglaze the pan by stirring and scraping up any browned bits from the bottom. Simmer until all the liquid evaporates. Return all the onions to the baking sheet and let them cool to room temperature. This can be done up to two days ahead and refrigerated or frozen.
In a large mixing bowl, combine the garlic, bread cubes, onions, and the remaining 1 1/2 teaspoons salt and 1/4 teaspoon black pepper. Spread evenly in the prepared baking dish.
In the same mixing bowl (so you don’t have to dirty another one), beat together the eggs and half-and-half. Pour evenly over the bread, pressing down with a rubber spatula or your hands to make sure the bread soaks up the liquid.
Place a sheet of plastic wrap over the top of the baking dish, then set another similar-size pan on the top of the bread mixture to press the bread down into the liquid. Put the pans in the refrigerator and let rest for 1 hour (so the bread absorbs the egg mixture).
Heat the oven to 350 degrees F. Remove the baking dish from the refrigerator, remove the top pan and the plastic, and sprinkle cheese evenly over the top of the bread mixture. Bake for 40 to 50 minutes, until puffed and golden. Remove from the oven, cut into squares, and serve.