Preheat your oven to 200°C (400°F). Gather a baking sheet, a mixing bowl, and a spatula.
Trim the radishes by cutting off their stems and roots. If larger, halve or quarter them to ensure even roasting.
Place the prepared radishes in a mixing bowl and drizzle with olive oil. Toss gently with a spatula until they are well coated and glistening.
Spread the radishes evenly on the baking sheet in a single layer, making sure they aren’t crowded for proper caramelization.
Roast in the oven for 20-25 minutes, shaking the pan halfway through, until the radishes are tender and their edges are golden and caramelized.
While the radishes are roasting, grate about 1/4 cup of Parmesan cheese using a fine grater and prepare any herbs or lemon zest you like.
Once roasted, remove the radishes from the oven and transfer them to a serving dish.
Sprinkle the hot radishes evenly with the freshly grated Parmesan cheese, allowing it to melt slightly into their surface.
Finish with a pinch of flaky sea salt and freshly cracked black pepper. Add chopped herbs or a squeeze of lemon for extra brightness if desired.
Serve the roasted radishes while warm, enjoying the tender texture and crispy, cheesy top with each bite.