Preheat oven to 400℉ / 200°C. Cut the radishes in half, and place them facedown on a parchment-lined baking sheet. If the carrots are very fat, slice them lengthwise and place them next to the radishes (if they are thin like mine, leave them whole).Roast for 20-25 minutes, tossing every 10 minutes or so. When they are tender and blistered in places, remove from the oven, let cool for a couple minutes, then drizzle with olive oil and sprinkle with flaky salt. Enjoy warm, or refrigerate and eat throughout the week.