Roast the eggplant: Preheat the oven to 400°F (200°C). Line a large baking sheet with foil.
2. Step
Cut the eggplants in half lengthwise and place on the prepared baking sheet cut-side up. Drizzle with the olive oil and season with the salt and pepper.
3. Step
Roast the eggplant for 30–40 minutes, until tender.
4. Step
Meanwhile, make the farro risotto: Heat the olive oil in a medium saucepan over medium heat. Add the onion and sauté until translucent, about 8 minutes. Add the garlic and thyme and cook, stirring, for 2 minutes, until soft. Add the mushrooms and cook until soft, about 3 minutes. Stir in the farro, allowing the oil to coat each grain, and cook for 1 minute, until grains are lightly toasted.
5. Step
Pour in white wine and stir until it evaporates completely, 1 minute. Add 1 cup of the vegetable stock at a time and cook until the liquid begins to reduce before adding more, stirring occasionally, about 30 minutes total. The farro should be cooked through and creamy.
6. Step
Turn off the heat and stir in the butter, Parmesan, salt, and pepper until melted and well combined.
7. Step
Gently fold in the sweet peas and cherry tomatoes, then the parsley.
8. Step
Remove the eggplant from the oven and turn the broiler on high. Scoop out ¼ cup of flesh from each half and discard.
9. Step
Fill the eggplant halves with the farro risotto, dividing evenly. Sprinkle with the Parmesan cheese, then lay 2–3 slices of fresh mozzarella cheese on top. Drizzle with a bit of olive oil and sprinkle with salt and pepper.
10. Step
Broil the eggplant for 7–10 minutes, until the mozzarella is golden brown. Garnish with the parsley and serve warm.
