In-N-Out’s spread is one of the most talked-about secret sauces in fast food. Slathered on every burger and available for dipping Animal Style fries, this creamy, tangy, slightly sweet sauce is deceptively simple — but getting the ratios right is what separates a good version from a great one. This copycat recipe has been tested and refined to match the original as closely as possible.

The Secret

In-N-Out spread is essentially a Thousand Island-style dressing, but the specific balance of sweet, tangy, and savory is what makes it special. The white vinegar adds a brightness that regular Thousand Island lacks, and the sugar rounds out the acidity. The onion powder provides a subtle savory note that most copycat recipes miss entirely.

Pro Tips

• Use sweet pickle relish, not dill relish — this is a common mistake that changes the flavor profile completely.
• The sauce truly tastes better after sitting in the refrigerator for at least 30 minutes. Making it a day ahead is even better.
• Store in an airtight container in the refrigerator for up to 2 weeks.
• For Animal Style fries, drizzle this spread over french fries topped with melted American cheese and grilled onions.