Preheat oven/OTG to 200-degree Celsius. Line a baking tray with parchment paper.
In a large bowl, add olive oil, lemon juice, garam masala powder, black pepper and salt. Mix well.
Then add the cooked chickpeas to the bowl. Give a good toss. Make sure all the chickpeas are coated with the masala-oil mixture.
Spread the chickpeas out in an even layer on the lined baking tray.
Roast/bake the chickpeas for 30-40 minutes or until they become crisp and golden brown. Don’t forget to give them a stir occasionally, like every 10-15 minutes or so.
Then take them out and serve immediately.