Preheat your oven to 200°C/180°C(fan)/400°F/Gas 6.
Toss the broccoli florets with the oil, salt and pepper.
Line a large baking tray with baking paper and spread the coated broccoli over the tray in a single layer.
Roast for 20 minutes.
Notes
Make sure your broccoli is really dry after washing. If it has too much moisture on it, then it won't crisp up in the oven.
Make sure that all the broccoli florets are cut to the same size, so that they all cook evenly. Make sure you are using mainly the broccoli heads and not the stalks, as they don't taste as good. Don't throw the stalk though - it can be grated for broccoli slaw.
If you want to make these look a little fancier when serving, then add a sprinkling of pine nuts for some added crunch.
Add a kick of heat by finishing the dish off with a sprinkling or red chilli flakes.
Make sure you don't overcrowd your baking tray. If the broccoli is too close together, then it will steam rather than roast and it won't get as crispy.
Flip the broccoli half way through to ensure it all gets nice and crispy.
For extra flavour, top it with everything bagel seasoning before serving.