Wash radishes, cut off tops and cut radishes in half. Save the greens if you want to sauté with radishes if not simply throw away.
Add radishes to a large skillet and fill with water just to the tops of the radishes. Bring to a boil and cook for about 5 minutes just until they start to soften but don't completely lose their color. Drain the radishes.
In the same skillet add the butter and let cook over medium heat until the butter becomes nutty and browned. Throw in the radishes and the radish tops if desired. Cook until slightly caramelized and throw in lemon zest, juice, thyme, pepper and Kosher salt.
Serve warm as a side dish or a full meal if you're feeling all that vegetable love.