Preheat the oven to 350. Place walnuts on a sheet pan in a single layer. Toast for 8-10 minutes. They should smell fragrant. Remove from oven and pan by placing the walnuts on a cutting board or on a plate. Set aside to cool.
Trim the end of the each endive and separate the leaves. Use the largest leaves for the appetizer and save the smallest ones for your next salad. Set aside.
Add the chopped blue cheese and pear to a small bowl and mix gently. Set aside. Chop the walnuts to a fine chop.
To Assemble:
On each endive leaf, spoon about 1 1/2 tsp of the pear/cheese mixture on the blunt end of the leaf. Sprinkle 1/4 tsp of finely chopped walnuts over the pear/cheese mixture on each leaf. Drizzle 1/8 tsp of balsamic vinegar over the walnuts on each piece of endive. Sprinkle each piece with fresh thyme leaves.