Preheat the oven to 375°F (190°C/gas 5) and line a baking sheet with parchment paper.
In a large bowl, add the broccoli, olive oil, and onion soup mix. Using your hands, toss to coat evenly. Spread the broccoli in an even layer on the baking sheet.
Roast until the broccoli is soft and the edges are crispy, about 30 minutes. Transfer the baking sheet to a heatproof surface and let the broccoli cool slightly, about 5 minutes.
Eat the broccoli right off the pan, like my family does, or transfer to a serving dish.