Place a rack in the center of your oven and preheat to 425°F. Line a baking sheet with parchment paper.
Trim off the tips and stems of the radishes. Discard the tips (if the greens are attached, see notes). Slice the radishes in half stem to tail (or quarters if some are much larger than the others), and place them on the baking sheet.
Toss with the oil, 1 tablespoon of the melted butter (or 1 tablespoon additional oil), kosher salt, and pepper until evenly coated. Spread into an even layer, then turn the radishes so the largest cut side is touching the pan.
If making the honey butter, while the radishes roast, in a small bowl combine the butter and honey.
Roast the radishes until they are crisp-tender and turning translucent, about 20 to 25 minutes. Drizzle with the honey butter and top with the flaky salt and chives. Enjoy hot or at room temperature.
Notes
If your radishes still have the green tops attached and those tops look fresh, you can roast these too! After trimming them from the radish (leave the stems attached, wash and dry them well. Toss them with the radishes on the sheet pan.
TO STORE: Refrigerate roasted radishes in an airtight container in the refrigerator for up to 3 days. While you can also freeze roasted radishes for up to 3 months, it’s not ideal; their texture will suffer after freezing, thawing, and reheating.
TO REHEAT: You can eat them cold, let them come to room temperature, or reheat them in the microwave, in a 350ºF oven, or in the air fryer.