Use this sauce to make Biang Biang Noodles with this recipe from Mission Chinese Food's Danny Bowien.
Place dried shrimp in a medium bowl; add enough water to cover by at least 1 inch. Repeat process with scallops; let stand overnight.
Drain dried shrimp and scallops; discard liquid and coarsely chop each. Transfer shrimp to the bowl of a food processor; pulse until finely chopped. Set aside. Repeat process with scallops, bacon, and sausage; set each aside.
Heat 1 cup canola oil in a large heavy-bottomed skillet over medium-high heat. Add shallots and cook, stirring, until soft and translucent, about 30 seconds. Add crushed red pepper flakes and cook 1 minute more. Add garlic, ginger, star anise, and cinnamon; stir to combine.
Increase heat to high; season with salt and add soy sauce. Add sausage, bacon, shrimp, and scallops, stirring after each addition.
Add remaining 1/2 cup oil; reduce heat to low and simmer until oil is infused, about 30 minutes, stirring every 5 minutes. Remove from heat and let cool before transferring to an airtight container. XO sauce may be kept refrigerated, up to 1 month.