Name: In‑N‑Out Copycat Animal Style Fries
Prep time: 5 min
Cook time: 35 min
Total time: 40 min
Cuisine: American
Ingredients: For the special sauce:; ¼ cup mayonnaise; 1½ tablespoons ketchup; 1 teaspoon rice vinegar or white vinegar; 1 tablespoon sweet relish; ½ teaspoon sugar; ½ teaspoon chili flakes (optional); For the fries:; ½ bag frozen French fries (about 300–350 grams); 2–3 slices American cheese or ½ cup shredded cheddar cheese; 1 large yellow onion, finely diced; 1 tablespoon butter; 1 tablespoon neutral oil (vegetable or canola); Pinch of salt

Jump to Recipe·Leave a Review

I love how this recipe brings the iconic In‑N‑Out Burger “Animal Style” fries experience right into my kitchen. With crispy golden fries, sweet caramelized onions, gooey melted cheese, and a creamy, tangy special sauce, this dish tastes just like the fast-food favorite—but I make it fresh at home with simple ingredients. In‑N‑Out Copycat Animal Style Fries

Why You’ll Love This Recipe

I really enjoy making this recipe because:

It satisfies those fast-food cravings without needing to leave the house.
I can control the ingredients and customize the flavor.
The combination of cheese, onions, and special sauce over crispy fries is just irresistible.
It’s an easy way to elevate plain frozen fries into something extra indulgent.
It’s a crowd-pleaser—I love serving it for movie nights, game days, or even just when I want something comforting and flavorful.

Ingredients

(Here’s a tip: Check out the full list of ingredients and measurements in the recipe card below.)

For the special sauce

¼ cup mayonnaise
1½ tablespoons ketchup
1 teaspoon rice vinegar or white vinegar
1 tablespoon sweet relish
½ teaspoon sugar
½ teaspoon chili flakes (optional)

For the fries

½ bag frozen French fries (about 300–350 grams)
2–3 slices American cheese or ½ cup shredded cheddar cheese
1 large yellow onion, finely diced
1 tablespoon butter
1 tablespoon neutral oil (like vegetable or canola oil)
Pinch of salt

Directions

In a skillet over medium-low heat, melt the butter and oil together.
Add the finely diced onion and a pinch of salt. Cook slowly, stirring every few minutes until the onions turn golden brown and fully caramelized. This takes at least 30 minutes—sometimes more. I make sure to keep the heat low so they don’t burn.
While the onions are cooking, I prepare the special sauce by mixing the mayonnaise, ketchup, vinegar, relish, sugar, and optional chili flakes in a bowl. I stir it well and set it aside.
Cook the frozen fries according to the package instructions. I usually bake them in a hot oven until they’re golden and crispy.
Once the fries are cooked, I place them on an oven-safe dish or tray. I top them with slices of American cheese or a generous sprinkle of cheddar cheese.
I broil the fries for 3–5 minutes until the cheese melts beautifully.
To finish, I spoon the caramelized onions over the melted cheese, drizzle with the special sauce, and serve immediately while everything is hot and melty.

Servings and timing

Servings: 2 to 3
Prep time: 5 minutes
Cook time: 30–35 minutes
Total time: 35–40 minutes

Variations

I can swap frozen fries for hand-cut, homemade fries if I want a fresher texture.
Using sweet potato fries gives the dish a different twist with a hint of sweetness.
If I want it extra cheesy, I double the amount of cheese and mix types—cheddar and mozzarella blend really well.
I sometimes leave out the chili flakes in the sauce when I want a milder flavor, or add more if I want heat.
For a vegetarian-friendly version, I just make sure all products (like mayo and cheese) are plant-based.

Storage / Reheating

I store leftovers in an airtight container in the fridge for up to 2 days.
To reheat, I preheat the oven to 200°C (390°F), spread the fries on a baking tray, and warm them for about 8–10 minutes.
I avoid using the microwave because it makes the fries soggy.
If I’m planning ahead, I like to store the components separately—the fries, onions, and sauce—so I can reassemble them freshly when ready to eat.

FAQs

What type of cheese works best for this recipe?

I like using American cheese slices for a true copycat feel, but shredded cheddar works great too. Both melt nicely and add that creamy texture I’m looking for.

Can I use fresh potatoes instead of frozen fries?

Absolutely. I peel and cut potatoes into thin fries, then bake or deep fry them. It takes a bit more time but gives a homemade texture I really enjoy.

How do I know when the onions are properly caramelized?

I look for a rich golden-brown color and sweet aroma. It takes around 30 minutes on low heat, and I stir regularly to make sure they cook evenly and don’t burn.

Can I make the special sauce ahead of time?

Yes. I often mix the sauce in advance and store it in the fridge in an airtight container for up to 3 days. The flavors actually deepen over time.

Are there healthier ways to make this recipe?

Yes. I bake the fries instead of frying them, use reduced-fat mayo, and go light on the cheese and sauce if I want to make a lighter version. But honestly, I usually enjoy it as a treat just the way it is.

Conclusion

This copycat Animal Style Fries recipe brings one of my fast-food favorites into my own kitchen with minimal effort. The rich flavors of caramelized onions, creamy special sauce, and melted cheese over hot, crispy fries are just too good to resist. I love how simple and customizable this dish is—it’s become one of my go-to indulgent snacks or side dishes.

In‑N‑Out Copycat Animal Style Fries