This is a variety of Radish called Easter Egg. They are able to grow much larger than most without getting pithy. I recently boasted about how much I don't like Radishes. I tried these, and have changed my mind. They're quite yummy, especially the white ones. If you like cooked cabbage, you should love this recipe.
Wash and pat the radishes dry.
Slice the radishes.
Drizzle with Olive Oil, and sprinkle Sea Salt to taste.
Preheat oven to 500 degrees. Roast for 30 min. or until they are as done as you like.