In a skillet large enough to hold endive in one layer, melt butter over medium-high heat. Add endive, and cook, turning occasionally, until brown all over, about 7 minutes.
Cover with a parchment-paper round, and then a tight-fitting lid. Reduce heat to very low, and cook until tender when pierced with the tip of a knife, 20 to 30 minutes. Season with salt and pepper, and serve immediately.