Preheat oven to 400 degrees Fahrenheit (200 degrees Celsius).

Thoroughly dry chickpeas using paper towels to remove all surface moisture; remove and discard any loose skins to ensure uniform roasting.

Place chickpeas on a rimmed baking sheet and toss with olive oil and sea salt until evenly coated.

Roast for 35 to 40 minutes, agitating the pan every 15 minutes, until chickpeas are golden brown and have achieved a firm, crunchy texture.

Remove from oven and immediately transfer to a bowl; toss with dry ranch seasoning and garlic powder while the oil is still hot to ensure adherence.

Spread chickpeas back onto the baking sheet and allow to cool completely at room temperature to finalize the crisping process.