Preheat a stove top grill. Season the eggplant with salt, pepper, and drizzle with 2 tablespoons oil. Grill until tender, cool, then cut into smaller pieces and set aside.
Heat a pan with remaining oil, add the garlic, stir for about 10 seconds or until slightly toasted but careful not to burn them. Add the mushrooms and peas, frequently stir until the mushrooms are tender.
Add the grilled eggplant and simple marinara, stir to mix, lower the heat, cover, simmer for 3 minutes.