Preheat oven to 400 degrees F. Line a rimmed baking sheet with foil (or use a silicon mat, like I did).
Combine peppers with 2 tablespoons olive oil. Season with salt and pepper; toss to coat evenly.
Place peppers, skin side up, on prepared baking sheet; cover tightly with foil. Roast until completely tender and wilted, about 25-30 minutes.
Meanwhile, pulse bread, parsley, basil, oregano, garlic, and 3 tablespoons oil in a food processor until fine, bright green breadcrumbs form. Season to taste with salt and pepper. Set aside.
Uncover peppers and turn skin side down. Divide breadcrumb mixture among peppers. Drizzle topping and remaining 1 tablespoon olive oil.
Roast, uncovered, until peppers begin to caramelize and breadcrumbs turn a deep golden brown, 30-40 minutes. (Peppers will start to darken on the bottom -- that's okay.)
Transfer peppers to a serving plate.
Serve warm or at room temperature. These can be made 4 hours in advance and be kept at room temperature.
Notes
* The amount of breadcrumbs you use will depend on the size of your peppers. The crumb mixture freezes well, so no worries if you end up with extra.
Recipe by story of a kitchen at https://www.storyofakitchen.com/vegetable-recipes/roasted-peppers-with-herbed-breadcrumbs/