Cook the bacon in a 10-inch nonstick skillet over medium heat until it has rendered some of its fat, about 3 minutes. Add the sweet potato and 1/4 teaspoon each salt and pepper. Cook, stirring, until the sweet potato is tender and the bacon starts to crisp, 6 to 8 minutes. Stir in 2 tablespoons of the chives and season with more salt and pepper to taste. Let cool for a couple of minutes.

Slice the bottom 1/2 inch off the endives so some of the outer leaves break free. Cut another 1/2 inch off and break some more leaves free. Keep going until all the larger leaves are free. (You should have about 20.) If you like, trim the leaves so they're all the same length. Save the remaining endive for a salad.

Set the endive leaves on a large platter. Spoon the sweet potato mixture near the base of the leaves. Top each with a dollop of the creme fraiche and then sprinkle with the remaining chives. Serve immediately or let sit for up to 20 minutes before serving.