Remove the papaya from the skin, cut into small pieces and combine with the yogurt, chervil and chili powder in a bowl. Season to taste with salt and set aside.
Heat two skillets on a medium heat. Divide the ghee between the two. In one of the skillets, sear the meat for 1 minute on each side, and then remove from the heat and let it rest in the skillet.
Sauté the apple and pear slices in the second skillet for 2 minutes. Stir in the chicory and radicchio and continue to cook for 2 minutes. Season with salt.
Cut the rolls in half and warm briefly on a toaster. Layer the bottom halves first with the fruit and chicory and radicchio and then the meat. Spread the papaya yogurt over everything and then place the upper halves of the rolls on top.