Preheat the oven to 350 degrees.

Peel the pears, cut them into quarters, and slice each quarter into thirds. Add the lemon juice.

Cut 8 pieces of parchment paper (or aluminum foil) into squares large enough to hold 1 ounce of goat cheese and 1 pear’s worth of slices and leave a 2-inch border all around. Lightly brush 4 squares of the paper with olive oil. Arrange the pear slices in the center of a square and spread 1 ounce of the goat cheese over each pear. Crumble the blue cheese over the goat cheese and pear slices, drizzle with oil, sprinkle with chervil, and season with salt and pepper to taste.

Place the remaining parchment squares on top of the others and fold up the edges to form packets. Simply double folding each of the four sides is enough to seal each packet. Put the papillotes on a baking sheet, and bake in the preheated oven for 12 to 15 minutes.

For the sauce: Peel the pear, cut it into small pieces, and mix with the yogurt and lemon juice. Season with salt and pepper to taste. Set aside.

To serve the papillotes, open each packet and slide the contents onto a dish while they are still warm. Serve with your choice of greens and the yogurt sauce on the side.