Add all the dry ingredients (except the oil) in a large heatproof bowl. Mix well.
Meanwhile, heat the neutral oil in a saucepan over medium low heat until small bubbles start to appear and the oil is hot, around 200 to 225F/100 to 110C.
You can test the heat by dipping a wooden chopstick and it should form bubbles or you can also drop a few chili flakes to see if it immediately sizzles.
(Note: when the oil is too hot or starts to smoke, I recommend to turn off the heat and allow for the oil to cool down slightly before pouring it over the dry mix. Oil that's too hot cause burn the sediments and create a bitter chili oil.)
If it the chili flakes dropped in the oil immediately sizzles, it’s good to go. Turn off the heat of the pan and carefully pour the oil over the dry chili mix.
Mix everything well.
Taste the sediments and feel free to season with more salt and sugar to taste, if needed. If you want more spice, you can add more chili powder/gochugaru.
To store: Leave the mixture to completely cool before transferring to a jar with a lid. Seal tight and store in room temperature in a cool, dry place. Use a clean spoon every time you scoop some of the chili oil to prevent any contamination. I usually keep mine for 3 to 6 months depending on how fast I consume my chili oil.
Use for: Your favourite noodles, dipping sauce, stir-fries, and more! You can use the oil for stir-frying or even scoop up some of the sediment and use as a base for your stir-fries or other dishes.