Prepare a large heatproof bowl (enough to hold 2 cups of oil) and layer it with a strainer.
Heat a heavy-bottomed pot or high-walled pan (*Footnote 5) over medium heat and add the oil.
Once the oil has reached 200 to 250°F (94 to 120°C), add the shallots and garlic. Cook, stirring frequently, until they just start to show color, about 12 minutes.
Add the minced chilis. Fry for another 5 minutes, or until the aromatics turn golden and crispy. (*Footnote 6)
Strain the aromatics using the prepared bowl with the strainer. Pour the oil back into the pot and set aside the cooked aromatics.
Heat the oil again to 200 to 250°F (94 to 120°C). Add the shredded scallops. Cook, stirring constantly, for about 10 minutes, until they just start to brown.
Add the minced shrimp and continue to fry for 5 minutes.
Add the minced ham. Cook and stir until everything turns a deep golden brown, 10 more minutes or so.
Return the fried aromatics to the pot and stir to mix well.
Pour in the Shaoxing wine. Add 2 tablespoons of the shrimp soaking liquid along with the sugar, oyster sauce, chicken powder, and chili flakes. Cook for another 5 minutes, or until the ingredients turn a dark brown color and the scallops are withered.
Remove the skillet from the stove. Transfer everything to a heat-proof container.
Once the sauce has cooled completely, you can store it in an airtight container or a jar in the fridge for about a month, or 3 months in the freezer.