In a medium bowl, measure ½ cup of full-fat mayonnaise and ½ cup of sour cream. These are the main ingredients for the sauce. You can use them at room temperature or cold.

Add 1 tablespoon of ranch seasoning mix, 1 tablespoon of blackened seasoning, ½ teaspoon of garlic powder, ½ teaspoon of onion powder, and ½ teaspoon of smoked paprika. If you like some heat, add a pinch of cayenne pepper. You can add more cayenne later if you want it spicier.

Roll a lemon on the counter for a few seconds to get more juice. Cut the lemon and squeeze about 1 teaspoon of juice into the bowl. Use your fingers or a small strainer to catch any seeds.

Whisk all the ingredients together until the sauce is smooth and creamy. Take your time. Whisking for about 1 minute helps evenly distribute the seasonings and prevents clumps.

Use a clean spoon to taste the sauce. If you want a stronger smoky flavor, add more blackened seasoning. If the sauce is too thick, add a tiny splash of buttermilk or water. If it needs more tang, add a few more drops of lemon juice. Make changes in small amounts to keep the flavors balanced.

Cover the bowl or transfer the sauce to an airtight jar. Refrigerate for at least 30 minutes. Chilling helps the flavors mix and makes the sauce thicker. The flavor will improve after chilling compared to right after mixing.