Place the egg yolks, mustard, and vinegar in a food processor. Blend on medium speed for 1-2 minutes.
Slowly drizzle oils into the mixture, one tablespoon at a time. If the marinade becomes too thick, add 1-2 tablespoons of warm water. Once all of the oil has been incorporated, add seasoned salt, garlic powder, onion powder, lemon pepper, celery salt, and black pepper until incorporated.
Store covered in the refrigerator until needed.
Yield: 2 1/2 cups