French onion soup knows how to treat an onion right, and pairs it with two excellent companions: cheese and bread. This appetizer is a celebration of that soup, and uses all of the usual components, but eliminates the broth. Whatever you want to call it—“deconstructed” or a “crostini”—it’s going to be your next favorite caremalized onion nosh.
There are two ways to construct this bite: onion as the cup, or onion as the topping. Your preference and the size of the onions used will dictate which way you put it together. Top and tail two or three onions, and peel off the tough outer paper. I used some red and some white. Cut the onions in half vertically from end to end. Scoop a small amount of softened salted butter into your hands and rub each onion half so the outside and cut side get coated. Place them, cut-side down, on an unlined baking sheet. The more seasoned the baking sheet, the better, as this will aid in caramelization and color.
After initial roast, onions split into two sections: outer layers and inner layersPhoto: Allie Chanthorn Reinmann
Bake the onions in a 400°F oven for about 15 minutes, or until the bottoms are sizzling and browned. Let the onions rest until they’re cool enough to handle. Peel the onion layers apart so you have at least two portions: one that consists of a couple of the outer layers, and another made up of the remaining inner layers. For large onions, you might peel every two layers and end up with three or four cups. For small onions or shallots, count two layers from the outside, wedge your thumb in between the layers and peel the two pieces apart. Now you have an onion cup, and an onion center.
Place each onion segment on a small slice of bread. I used a sesame Italian loaf sliced about a half an inch thick. Alternatively, for large onion layers, you can make the onion the vehicle. Rip the bread into chunks and tuck them into the onion cups. Shred or peel gruyère into strips and top each onion with a sprinkle of thyme and a dose of cheese. Pop the onions back into the oven for about five minutes, or until the cheese is fully melted and bubbling. Salt and pepper each onion round and serve while warm.
Reverse assembly option on the left with torn bread inside the onion cup.Photo: Allie Chanthorn Reinmann
The onions become mellow and sweet, the cheese adds nuttiness and a welcome chewy texture, and the crunchy-soft bread with thyme ticks all the flavor boxes of French onion soup. These are best eaten right away, and make a good companion for a dry red wine.
French Onion Flats
Ingredients:
3 small onions, peeled and halved from end to end (red or white)1-2 tablespoons salted butter, softened10-12, ¼ -inch slices bread (baguette or Italian)1-3 sprigs thyme ½ cup grated or shaved gruyèreLiberal pinches of salt and pepperPreheat the oven to 400°F.
Coat the onions in butter with your hands and lay them, cut-side down, on an unlined baking sheet. Bake for 15 minutes, or until the bottoms are caramelized.
Peel each onion half into two separate segments, one will be cup-shaped and the other will be the center of the onion. Place all of the onion rounds onto a slice of bread and sprinkle with a few thyme leaves. Cover each onion with some cheese, and return to the oven for about five minutes, or until the cheese is melted and bubbly. Salt and pepper the onion cups before serving.
