Place the flour into a large mixing bowl. Add in the hot boiling water and stir with a pair of chopsticks until it forms a shaggy dough. Sprinkle in the instant yeast.
Use your hands and knead until the dough becomes smooth.
Transfer to a lightly oiled bowl and cover. Let rest at room temperature for 30 minutes.
Prepare the meat filling:
In a medium bowl, add the ground pork, salt, garlic, ginger, onion, green onion and stir until combined.
Add in the ground Sichuan peppercorn, chili oil, sesame oil, soy sauce and mix until everything is incorporated.
Assemble:
Divide the dough into 8 equal portions.
Roll out the dough into a long rectangle. Smear approximately 1 tablespoon of meat filling over the surface of the dough.
Roll up the dough into a cigar. Turn the dough 90 degrees.
Roll the dough again so it coils into a snail-like shape. Flatten the coil with the palm of your hand so it now looks like a pancake with swirls. Scatter some sesame seeds on top of the dough.
Use a rolling pin to even out the dough. Flip and add a little more sesame seeds to the other side. You should obtain a disc about 4" in diameter.
Repeat with the remaining dough.
Cook:
Preheat oven to 300°F/149°C.
Heat up a frying pan over medium high heat with about 2 tablespoon of oil.
Place the dough discs into the frying pan (depending on the size of your pan, you may be able to fit 2-3 pieces).
Fry for about 5-6 minutes per side, until crisp and golden brown. Remove and drain on a paper towel. Repeat with the rest of the dough.
Place the pan-fried guo kui onto a baking sheet lined with parchment paper and keep in the oven to warm until ready to eat.
Serve warm with additional chili oil, and garnish with cilantro and green onion.