1 leek, thinly sliced
1 yellow onion, thinly sliced
1 stalk celery, thinly sliced
2 shallots, thinly sliced
2 tablespoons chopped garlic
1 tablespoon granulated garlic
1 tablespoon granulated onion
6 cups low-sodium vegetable broth
9 medium Yukon gold potatoes, peeled and very thinly sliced
1 tablespoon chopped, fresh flat-leaf parsley, or 1 teaspoon dried
1 tablespoon chopped fresh thyme, or 1 teaspoon dried
Preheat the oven to 350º F. Put the leek, onion, celery, shallots, and garlic in a large dry saucepan over medium heat and cook, stirring constantly, until the onion starts to brown, about 5 minutes.
Stir in the granulated garlic and granulated onion and cook for 2 minutes. Stir in the broth, increase the heat to medium-high, and simmer until the liquid is reduced by half.
Add the potatoes and stir until well combined. Decrease the heat to low and cook, stirring constantly so the potatoes don’t stick together, until the potatoes are translucent, about 15 minutes.
Remove from the heat and stir in the parsley and thyme. Transfer to 13×9-inch baking dish and bake uncovered for about 25 minutes, until the potatoes are golden brown and fork-tender. Serve hot.