Preheat the oven to 500°. Using a paring knife, pierce the eggplants in several places. Put them on a large baking sheet along with the red pepper and roast the vegetables until tender and the skins darken, about 25 minutes.
Remove the roasted vegetables from the oven. Working over a bowl, peel the pepper as soon as it is cool enough to handle. Remove the stem and seeds and discard but allow any pepper juices to fall into the bowl. Cut the red pepper into 8 rough squares of equal size. Peel the eggplants and remove as many seeds as possible from the flesh; keep the flesh in thick strips. Drain in a colander set over a plate for about 10 minutes, then cut the eggplants into coarse chunks.
Bring a large saucepan of water to a boil. Have ready a large bowl of ice water. Working with 3 or 4 Swiss chard leaves at a time, hold them by their stems and dip them into the boiling water for about 30 seconds, just until they wilt. Plunge the wilted leaves into the ice water. Repeat with the remaining chard. Remove the leaves from the ice water and drain on paper towels. Cut off the stems and reserve them for another use.
In a large nonreactive skillet, heat the olive oil over low heat. When hot, add the shallot and cook, stirring, until softened, about 4 minutes. Add the garlic and scallion and cook, stirring, until fragrant, about 1 minute. Add the tomatoes and increase the heat to moderate. Cook the tomatoes, stirring, until most of the liquid has evaporated, about 3 minutes. Stir in the reserved pepper juices, the eggplants, lemon juice, rosemary and thyme. Season with salt, black pepper and cayenne. Transfer the vegetable mixture to a large plate and let cool.
Generously butter eight 1/2-cup ramekins. Cut any tough veins from the chard and halve the leaves lengthwise. Thickly line the ramekins with the chard leaves, allowing about 1 inch of overhang. Put about 3 tablespoons of the eggplant mixture into each ramekin and then top with a red pepper square, pressing lightly. Cover with another 3 tablespoons of the eggplant mixture, using up the remainder. Fold the overhanging leaves over the eggplant mixture and press lightly.
Preheat the oven to 350°. Set the ramekins in a roasting pan and pour enough hot water into the pan to reach halfway up the sides of the ramekins. Cover with foil and bake for about 20 minutes, or until a knife tip inserted in the center of a timbale comes out hot. The timbales can be kept in their water bath for up to 20 minutes. To serve, wipe the ramekins dry and gently invert them onto dinner plates; the timbales should fall out easily.