Trim the stem end of the zucchini, cut them in half lengthwise, and scoop out a small channel of seeds with a regular teaspoon. Place the zucchini in one layer on a sheet pan, brush generously all over with olive oil, and turn the zucchini cut-side down. Sprinkle with 1 teaspoon salt and roast for 12 to 15 minutes, until just tender but still firm when tested with the tip of a small paring knife.
Meanwhile, make the bread crumbs. In a medium bowl, combine the garlic, parsley, basil, Parmesan, 1 teaspoon salt, and 1/2 teaspoon pepper. Add the panko and 3 1/2 tablespoons of oil and mix well.
Turn the zucchini cut-side up and spoon a heaping tablespoon of the panko mixture evenly on each zucchini. Bake for another 8 to 10 minutes, until the panko is crispy. Serve hot, warm, or at room temperature.
Make ahead: Prepare the zucchini and the crumb mixture separately and refrigerate for up to a day. Roast before serving.
