Oven preparation: Set the oven to 425°F (220°C) and line the large baking tray with parchment paper or grease it lightly with olive oil.
For the cabbage, remove any of the outer leaves that are damaged and cut it into 6 to 8 thick wedges, leaving a bit of the core on so that the wedges stay together.
To make the seasoning oil, take a small bowl and mix into it 2 tablespoons of olive oil, some minced garlic, smoked paprika, cumin, salt, black pepper, and dried thyme if you are using it.
Season the cabbage by generously brushing the seasoned oil over both sides of each cabbage wedge and then place the wedges, cut side down, on the baking sheet.
To prepare the chickpeas, drain and rinse them thoroughly, then pat them very dry using a clean kitchen towel and remove any loose skins if you want to.
To season the chickpeas, mix them with 1 tablespoon of olive oil, smoked paprika, garlic powder, cumin, salt, and black pepper and stir until they are evenly coated.
Begin roasting: roast the cabbage for 15 minutes and then add the seasoned chickpeas to the baking sheet, placing them in a single layer with space left between the ingredients.
Keep roasting: roast the dish for an additional 20 to 30 minutes, and halfway through this time turn the cabbage wedges with care. Stir the chickpeas once or twice. By the end of this process the cabbage should be tender with deep golden edges and the chickpeas should become golden and crunchy. If the chickpeas still need to be crisped up, then remove the cabbage when it's ready and roast the chickpeas for an extra 5 to 10 minutes.
Finish off the dish by moving the roasted cabbage to a serving plate and spreading the crunchy chickpeas over and among the wedges. Then squeeze the fresh lemon juice over the food and dot it with some chopped parsley.
Serve it straight away; enjoy the cabbage while it is still warm and tender and the chickpeas when they are crispiest