1 large sweet potato, peeled and cut into eight 1/2-inch rounds
1 eggplant, cut across into eight 1/2-inch rounds
3 red onions, cut across into 1/2-inch rounds
1/4cup good- quality olive oil
Salt and pepper
3/4cup ricotta cheese
Grated zest and juice of 1 lime
Chopped fresh basil for garnish
Instructions
Start the coals or heat a gas grill for medium-high indirect cooking. Make sure the grates are clean.
Brush the vegetable slices with the oil, coating them completely; sprinkle with salt and pepper on both sides. Whisk the ricotta and lime zest and juice together in a small bowl with some salt and pepper. Taste and adjust the seasoning.
Put the onions on the grill first, directly over the fire. Close the lid and cook, turning once, until the slices brown and are soft all the way through, 8 to 10 minutes per side. Check them a few minutes after you put them on; if they’re coloring too quickly, move them to a cooler part of the fire. Put the sweet potato on the indirect side of the grill and cook, turning once, until you can pierce them all the way through but they’re not mushy, about 6 minutes per side, then move them directly over the fire and cook, turning once, until brown, about 2 minutes per side. Put the eggplant over direct heat and cook, turning once, for 5 to 8 minutes per side; it’s done when brown and tender. Transfer everything to a platter as it finishes.
To make stacks, start with eggplant on the bottom, followed by onion, then sweet potato; repeat. Top each stack with a generous dollop of lime ricotta, garnish with basil, and serve with the remaining ricotta in a small bowl on the side.