1. Preheat oven to 450 degrees with racks in middle and lower thirds. On a rimmed baking sheet, toss tomatoes with 5 teaspoons olive oil, season with salt and pepper, and roast on bottom rack of oven until soft and skins have blistered and burst, about 30 minutes. On a separate, small baking sheet, spread bulgur in an even layer and toast on top rack of oven until fragrant and deep golden, stirring halfway through, 15 minutes. Transfer bulgur to a large bowl.

2. Add onion to the tomatoes, stir to combine, and season with salt and pepper. Roast until onion is soft and golden, flipping halfway through, about 15 minutes.

3. Meanwhile, cook bulgur according to package instructions. Transfer to the large bowl, season with salt and pepper, stir in chickpeas; let cool if still warm. Stir in parsley, tomatoes, onions, 1 tablespoon olive oil, and lemon juice to taste and transfer to serving platter. Serve warm or at room temperature with lemon wedges.