Preheat your oven to 200°C (400°F) and line a baking sheet with parchment paper.
Trim the green tops and root ends from the radishes, then slice them in halves or quarters depending on their size for even roasting.
In a small bowl, mix the sliced radishes with olive oil, salt, and black pepper until evenly coated.
Spread the radish pieces in a single layer on the prepared baking sheet, making sure they’re not crowded.
Roast in the oven for 20-25 minutes, shaking the pan halfway through, until the edges are golden and blistered, and the radishes are tender.
While the radishes roast, grate about 1/4 cup of Parmesan cheese into a small bowl and set aside.
Once the radishes are done, remove the baking sheet from the oven and sprinkle the grated Parmesan evenly over the hot vegetables.
Return the tray to the oven for an additional 3-5 minutes, until the cheese melts, bubbles, and forms a slightly crispy crust.
Remove from the oven and let rest for 2 minutes to allow the flavors to settle and the cheese to crisp up further.
Transfer the roasted radishes to a serving dish or plate, then drizzle lightly with olive oil or squeeze fresh lemon juice if you like a bright finish.
Enjoy the smoky, tender radishes with their cheesy, crispy crust as a flavorful side or snack.
