Place around 1 cup of red pepper powder in a bowl. Stir in 3 tablespoons of clean water. Combine and let the pepper flakes absorb the water. If you want a crispy version, then skip mixing in the water.
Pour around 3 cups of oil into a wok, add scallion, coriander, white onion, and smashed ginger first because they contain water. Heat over a slow fire until the aromatics begin to wither. Place all the spices in.
Continue heating with slow fire for another 6 to 8 minutes until the contents are all withered and browned. Take out all of the spices and aromatics.
Heat the oil for another 2 or 3 minutes until slightly smoky. Pour ⅓ of the oil to the bowl. Mix to combine.
Repeat the above process twice to add all oil to the pepper flakes. Add toasted sesame seeds.
Keep the chili oil in an air-tight container and this can be kept for up to one month at room temperature.
Video
Notes
The nutrition facts is calculated based on one bottom of the oil