In a small bowl, mix chili flakes, ground chili, salt, sesame seeds and black rice vinegar (or soy sauce). Have another deep, dry, heat-proof bowl ready (see note 4). Place a fine mesh strainer over it.
Pour oil into a small pan/pot. Add all the spices and aromatics. Simmer over low heat. Watch attentively. Turn off the heat immediately when the scallions turn brown (It took me about 20 minutes). Test the temperature with a thermometer (it needs to reach 350°F/175°C). Alternatively, drop in a few chili flakes to test. The oil is hot enough if they bubble and spin immediately.
Pour the oil into the empty bowl through the strainer. Discard everything caught in the sieve.
Add half of the chili mixture to the oil. You should see it bubbling intensively. Add the remaining when the bubbling calms down. Stir well with a clean dry spoon.
Leave to cool uncovered. Then transfer to a container of your choice. Wait for at least 12 hours before using it to allow all the flavors to combine.
Storage: The lifespan of chili oil is about 2 months in the kitchen cupboard (dry, cool and away from direct sunlight) and about 6 months in the fridge.
Usage: Both the oil and the chili flakes are for consumption. Use a clean spoon to stir well before serving. If your dish requires pure chili oil, use a strainer to filter out the chili and sesame seeds.
1. Ground chili is dried chili pepper in powder form. I don't recommend you use chili powder that contains other spices, salt, etc. Korean chili powder (the very fine type) or paprika are good options.2. It's fine to use only chili flakes if you can't find ground chili. But you shouldn't use ground chili alone for this recipe.3. If you don't have whole Sichuan peppercorn but ground Sichuan pepper, add ¼ teaspoon to the chili mixture.4. Use a glass or porcelain bowl since they cool down the oil more efficiently than metal ones. Make sure it is deep enough to avoid overflow when the chili mix is added to the hot oil.5. If short on time or ingredients, you may make the basic version:
Mix chili flakes, ground chili, ground Sichuan pepper (optional), toasted sesame seeds, and salt.
Heat the oil then pour it over the mixture. Stir well to cook evenly.
Try the advanced version whenever you have a chance. It is truly worth the effort!