Ingredients

• 1 tsp. kosher salt, divided, plus more
• 1 large sweet potato (about 1 lb.), halved lengthwise
• 1/2 fennel bulb (about 6 oz.), thinly sliced, plus fronds (for serving; optional)
• 1/2 small red onion, thinly sliced
• 1/4 cup apple cider, coconut, or unseasoned rice vinegar
• 3 Tbsp. extra-virgin olive oil, divided
• 1/2 lb. ground lamb
• 1 tsp. ground cumin
• 1/2 tsp. ground cinnamon
• 1 tsp. Aleppo-style pepper, plus more for serving
• 8 oz. wild mushrooms (such as oyster or shiitake), sliced into 1/4" slices
• 1/2 cup plain whole-milk yogurt
• 2 Tbsp. fresh lemon juice
• 1/4 cup mint leaves

Instructions

1. Fill a large pot with about 1" water; season with a big pinch of salt. Set a steamer basket in pot. Cover pot and bring water to a boil. Add potato, cover, and steam until fork-tender, 20–25 minutes.
2. Meanwhile, toss sliced fennel, onion, vinegar, and 1/4 tsp. salt in a medium bowl. Let sit, tossing occasionally, at least 10 minutes and up to 30 minutes.
3. Heat 2 Tbsp. oil in a large skillet over medium-high. Add lamb, cumin, cinnamon, 1 tsp. pepper, and 1/2 tsp. salt and press into an even layer. Cook, undisturbed, until well browned on the bottom, about 4 minutes. Break up into pieces with a spatula and continue to cook, stirring occasionally, until browned, 1–2 minutes. Push mixture to one side of skillet and add mushrooms in an even layer; season with salt. Cook, undisturbed, until beginning to brown and soften, 3 minutes, then stir together with lamb mixture. Continue to cook, stirring occasionally, until mushrooms are golden brown, about 2 minutes more.
4. Whisk yogurt, lemon juice, and remaining 1 Tbsp. oil and 1/4 tsp. salt in a small bowl.
5. Divide potato halves between bowls and mash slightly with a fork. Top with yogurt sauce and mushroom mixture. Lift fennel and onion out of vinegar with your hands and scatter over bowls; discard vinegar. Top with mint, fennel fronds (if using), and pepper.