01 - Preheat oven to 425°F. Line a baking sheet with parchment paper.
02 - Place halved radishes in a large bowl. Add minced garlic, olive oil, sea salt, black pepper, and thyme if using. Toss until the radishes are evenly coated with the oil and seasonings.
03 - Spread the seasoned radishes in a single layer on the prepared baking sheet, cut sides facing down for even caramelization.
04 - Roast for 20 to 25 minutes, stirring halfway through, until the radishes are golden and fork-tender.
05 - Transfer the roasted radishes to a serving dish and sprinkle with fresh chopped parsley if desired. Serve immediately.