Preheat the oven to 450 degrees.
In a large mixing bowl, toss the radish halves with 1 tablespoon olive oil, and season with salt and pepper.
Place the seasoned radishes on a baking pan, or in a cast iron skillet.
Roast the radishes for about 20 minutes, tossing occasionally, until they are tender and caramelized.
While the radishes are roasting, place the cannelloni beans in the same mixing bowl, add the additional tablespoon olive oil, the lemon juice, and garlic powder. Season with salt and pepper to taste.
When the radishes are roasted, add them to the bowl with the beans, and add parsley.
Sprinkle with feta cheese, and adjust seasonings as necessary.