Preheat the oven to 400 degrees F. Arrange two racks evenly spaced in the oven.
Remove and discard the bottom half of the broccoli stems. Cut the remaining stems in half lengthwise up to the florets and pull the florets apart. (Don't cut through the florets!) Continue cutting all the stems and pulling the florets apart - you want to have about two inches of stem with whole florets attached. Place the broccoli on two sheet pans, drizzle with 4 tablespoons of olive oil, sprinkle with 1 1/2 teaspoons salt and 1 teaspoon pepper. Toss well, spread in one layer on each pan, and roast for 15 minutes until crisp-tender and the edges are starting to brown, tossing occasionally.
Meanwhile, in a small (8-inch) saute pan over medium-low heat, heat 1 1/2 tablespoons of olive oil, add the garlic, and cook for 1 minute, until fragrant but not browned. Add the panko, tossing to coat in the oil. Cook over medium-low heat for 3 to 4 minutes, until the panko is golden brown, tossing occasionally. Off the heat, add the pine nuts and lemon zest.
Place the broccoli on a serving platter, sprinkle with the lemon juice, then the panko mixture, 1/2 teaspoon salt, and toss well. Serve hot, warm, or at room temperature.