Neutral oil, for frying (enough to halfway submerge the latkes, about 1/4-1/2 inch in the pan)
1 egg, whisked
1/4 cup all purpose flour
1/4 teaspoon baking powder
Chives, chopped, for garnish
For the mushroom gravy:
1/2–1 tablespoon neutral oil (enough to very lightly coat the pan)
2 cups (~6 ounces) brown mushrooms (or, alternatively shiitake, oyster, or white mushrooms), thinly sliced
3 cloves garlic, minced
2 tablespoons butter
2 tablespoons flour
1 cup mushroom or vegetable broth (or, alternatively, water)
Salt, to taste
Freshly cracked black pepper, to taste
Squeeze of fresh lemon juice, to taste
Instructions
Add grated potatoes and onions to a bowl, season with salt, and toss until thoroughly combined. Let sit for about five minutes. In the meantime, add enough neutral oil to cover half of the latkes in a skillet over medium heat. While the oil heats up (it should be shimmering but not smoking), use a towel to squeeze out as much liquid as possible from the potato-onion mixture then return it to the bowl. Add half of the whisked egg, all purpose flour, and baking powder and mix to combine. Once the oil is hot, shape the potato-onion mixture into patties and carefully transfer to the skillet. Cook until golden brown on the bottom (3-4 minutes), then flip and cook until golden brown on the other side. Transfer to a towel-lined rack to dry.
While the latkes cook, start the mushroom gravy if you’re making it. Add oil to a pan over medium-high heat. Add mushrooms and cook until browned, tossing as needed for even coloring. Reduce heat to medium and add minced garlic. Cook for 1-2 minutes, then transfer mushrooms and garlic to a bowl or plate and set aside. Add butter and flour to the pan and cook—stirring as you go—until it starts to smell nutty (this shouldn’t take too long). Add mushroom or vegetable stock to the pan (or, alternatively water), and season with salt and freshly cracked pepper. Once cooked to your preferred gravy consistency, remove from heat and add a squeeze of fresh lemon juice. Taste and adjust salt, pepper, and lemon juice as needed.
Transfer latkes to a serving plate and top with a generous amount of mushroom gravy, if using. Garnish with chopped chives.