In a saucepan, heat the neutral oil over medium heat until it reaches around 300°F (150°C). You can use a thermometer to monitor the temperature if available.
Once the oil is hot, carefully add the dried red chili flakes, minced garlic, Sichuan peppercorns, whole black peppercorns, bay leaves, cinnamon stick, and star anise to the saucepan.
Lower the heat to medium-low and let the spices infuse into the oil for about 10-15 minutes, stirring occasionally. This will allow the flavors to meld together. Next, add the salt and stir well.
Continue to cook the oil for another 5 minutes, stirring occasionally, to deepen the flavors.
Once the chili garlic oil is fragrant and the spices have infused into the oil, remove the saucepan from the heat and let it cool for about 10-15 minutes.
Using a fine mesh sieve or cheesecloth, strain the oil to remove the solids and transfer the infused oil to a clean, heatproof container or glass jar. Allow the chili garlic oil to cool completely before sealing the container.