Begin by preheating your oven to 200°C (390°F). Gather a baking sheet, a sharp knife, and a mixing bowl.
Wash the radishes thoroughly, then trim off the tops and roots. If your radishes are large, cut them into halves or quarters for even roasting.
Place the radish pieces in a mixing bowl, drizzle with olive oil, and sprinkle generously with salt and pepper. Toss everything together until the radishes are evenly coated.
Spread the radishes in a single layer on your prepared baking sheet, ensuring they aren’t crowded so they roast evenly.
Pop the baking sheet into the oven and roast for about 20-25 minutes. Shake or flip the radishes halfway through, watching for golden edges and tender insides.
While the radishes roast, grate about 1/4 cup of Parmesan cheese, which will be sprinkled on hot radishes for melting and crunch.
Once the radishes are nicely caramelized and tender, remove them from the oven. Immediately sprinkle the grated Parmesan over the hot radishes, allowing it to melt slightly.
If desired, return the tray to the oven for an additional 2-3 minutes to crisp up the cheese further, or serve as is once the cheese has melted.
Squeeze fresh lemon juice or zest over the radishes for a bright contrast, and sprinkle with chopped herbs if using.
Let the radishes rest for a couple of minutes, then serve warm, enjoying the tender, caramelized vegetables with their crispy cheesy crust.
