Add the sour cream, mayonnaise, salsa, lime juice, and ranch powder (if using) to a medium mixing bowl.
Whisk until completely smooth and evenly combined, making sure no streaks of sour cream or mayonnaise remain. Taste the dressing and adjust the flavor as needed with additional lime juice or salsa.
Serve immediately over taco salad or refrigerate until ready to use. Stir before serving if the dressing has been chilled.
Notes
Sour Cream: Can be substituted for plain Greek yogurt.
Mayonnaise: Any type of mayonnaise can be used for this recipe.
Salsa: Use your favorite kind of salsa or hot sauce.