1. Put the pear in a small bowl of cold water with 1 tablespoon of the lemon juice to prevent it from browning. Let sit for 5 to 10 minutes and then drain well.
2. In a medium bowl, toss together the beef, the remaining 2 tablespoons lemon juice, and the spring onions, pine nuts, sesame oil, shallots, lemon zest, and salt and pepper to taste. Gently stir 1/2 cup of the julienned pears into the tartare.
To serve: Arrange the tartare in the center of four plates. If desired, make a small well in each mound of beef and put an egg yolk in each. Top with the remaining pear and garnish with spring onions, pine nuts and chile threads. Serve immediately, with lotus root chips if desired.
Cook's Note: Feel free to serve with lemon wedges on the side instead of mixing in the juice. This will help keep the beef's red color intact, as the lemon juice will "cook" the meat slightly.