I've always loved my mom's version of aloo gobi, a classic Indian potato and cauliflower dish, because she roasts the vegetables before sauteing them to add an extra smoky, charred flavor and a crispy texture. This version swaps the cauliflower for Brussels sprouts, which char beautifully in the oven and really hold the whole spices. It's a great make-ahead party dish, as you can pre-roast the vegetables, then whenever you're ready to serve, it takes all of 10 minutes to reheat and finish them with the spices in the pan.
Preheat the oven to 400 degrees F. Line a rimmed baking sheet with aluminum foil.
Place the Brussels sprouts and potatoes on the prepared baking sheet and toss them with 3 tablespoons of the oil. Spread them in an even layer and roast until the vegetables are browned and crisped slightly, about 30 minutes, tossing halfway through. (The sprouts will brown more than the potatoes; that's okay.) Set the vegetables aside to cool.
Heat the remaining 2 tablespoons oil in a large skillet over medium heat. Once the oil begins to shimmer, add the coriander seeds, cumin seeds, turmeric and asafetida, if using. Cook, stirring, until the coriander and cumin turn a shade darker, no more than 1 minute. Add the roasted vegetables, including any charred bits from the foil, and gently mix everything together. Mix in the chile powder and 1 teaspoon salt, arrange the vegetables in a single layer, and cook until the vegetables are tender but not soggy and the Brussels sprout leaves are nicely charred, 6 to 8 minutes.
Remove from the heat and add the lime juice. Taste and adjust the seasoning with more lime juice and salt, if needed.