Using a medium bowl, add sour cream, mayonnaise, milk, lemon juice, chives, dried parsley and garlic salt; stir until well combined.

Add crumbled blue cheese; stir until well combined.

Cover and refrigerate for at least 4 hours (preferably overnight).

Using a mandolin, slice potatoes into 1/8” thick slices; place potatoes in a large bowl.

Cover potatoes with cold water and stir gently; drain water. Rinse potatoes until water runs clear.

Place potatoes in a large bowl. Add vinegar and enough cold water to cover. Let stand at room temperature for 1 hour.

Using a heavy-bottomed pot or a deep fryer, add 2-3” of oil. Heat over medium heat until temperature reaches 300°F. (If using a pot, a candy thermometer is the best way to monitor the temperature of the oil.)

Drain potatoes and transfer to a paper-towel lined baking tray. Pat potatoes dry with additional paper towels.

Working in batches, fry potatoes for 6-8 minutes, flipping occasionally, or until crispy. (Note: Avoid the temptation of putting too many potatoes in the pot at a time. Overcrowding the pot will make the chips take longer to fry, and they will taste greasier.)

Using a slotted spoon, transfer chips to a paper-towel lined baking tray. Sprinkle the batch of chips with a portion of the salt. Repeat process, allowing oil temperature to return to 300°F after each batch.