How to Make the Ultimate Umami-Bomb Vegetarian Demi-Glace
1/4 cup vegetable oil
One 2-pound bunch of celery, ribs peeled and cut into 2-inch lengths on the diagonal, leaves reserved
4 ounces thickly sliced bacon, cut into 1-inch pieces
1 cup canned peeled Italian tomatoes, drained and chopped
3 tablespoons brandy
Freshly ground pepper
In a medium skillet, heat the oil until shimmering. Add the celery leaves and fry over moderate heat until crisp, about 2 minutes. Transfer the leaves to a plate and sprinkle with salt.
In a large enameled cast-iron casserole, cook the bacon over low heat, stirring a few times, until the fat has rendered, about 6 minutes. Add the celery and stir to coat it with the bacon fat. Add the tomatoes and brandy, cover and cook until the celery is barely tender, about 10 minutes. Uncover and cook until the sauce thickens slightly, about 3 minutes. Season the celery with salt and pepper and transfer to a serving bowl. Top with the fried celery leaves and serve.