01 - In a medium bowl, whisk together mayonnaise and sour cream until completely smooth and well blended.
02 - Fold in minced jalapeños, jalapeño brine, garlic, cumin, onion powder, salt, and black pepper. Mix until evenly distributed throughout the sauce.
03 - Add fresh lime juice and chopped cilantro. Stir thoroughly to combine all ingredients into a uniform, creamy consistency.
04 - Cover the bowl and refrigerate for at least 1 hour to allow flavors to meld and develop. This resting period is essential for optimal taste.
05 - Remove from refrigerator, give the sauce a final stir, and serve chilled. Use as a dipping sauce for tortilla chips or drizzle over tacos, grilled meats, or fish.