Cover almonds with water and soak for 4 to 48 hours. Drain and rinse. Chop fine in a small food processor with ½ cup filtered water, mustard powder, salt, and pepper. Add lemon juice and vinegar and pulse until combined. With food processor running, slowly drizzle in ½ cup of the olive oil to create a creamy consistency. Add up to an additional ½ cup olive oil, if desired, to create a thinner dressing. Add seasoning of choice and pulse to combine. Taste and adjust seasoning if necessary. Thin out even more with additional water or lemon juice if desired. Dressing will become more flavorful the longer it sits. Store sealed in the refrigerator.
Use as a salad dressing, a sauce for fish, or a dip for veggies.