How to Make It
Melt butter in a large nonreactive sauté pan over medium. Add endives; season with salt and pepper. Cook, turning occasionally, until lightly browned, about 5 minutes.
Reduce heat to low. Add stock and 1 tarragon sprig. Cover and cook until endives are tender, about 20 minutes. Transfer endives to a plate.
Return pan to medium-high. Stir in the cream and cook, stirring often, until sauce has reduced to about 1/4 cup and coats the back of a spoon, 3 to 4 minutes.
Spoon the cream sauce onto a warm serving platter and arrange endives on top. Garnish with leaves from remaining tarragon sprig.