Trim radishes of stems and tails and wash thoroughly. Cut in half or quarters, depending on size. You're looking for bite size here. Pat dry with a paper towel.
In a medium size skillet over medium/high heat melt butter. When butter starts to foam add radishes and sauté for 8-10 minutes until starting to brown, turning once or twice. Add vinegar and parsley and toss to coat. Remove from heat and season generously with sea salt, pepper and a squeeze of fresh lemon juice. Serve immediately.