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How to Make a Perfect Roux for Sauces

Name: How to Make a Perfect Roux for Sauces
Ingredients: 2 tablespoons butter; 2 tablespoons all-purpose flour

A roux is equal parts fat and flour cooked together to thicken sauces. Melt butter in a heavy-bottomed pan, whisk in flour, and cook while stirring constantly until it reaches your desired color—from pale blonde for delicate sauces to deep brown for robust gravies. The key is steady heat and constant motion to prevent burning.

Difficulty: Medium

Ingredients

2 tablespoons butter
2 tablespoons all-purpose flour

Step by step

Measure equal weights of fat and flour. Use 2 tablespoons each of butter and all-purpose flour for about 1 cup of finished sauce. Weight matters more than volume here—flour can pack differently.
Heat the fat in a heavy-bottomed pan. Medium heat works best. Cast iron or enameled pans hold steady heat. Avoid thin pans that create hot spots and burn your roux.
Add flour all at once and whisk immediately. The moment flour hits fat, start whisking. Don't let it sit—lumps form fast. Use a flat whisk if you have one.
Cook while stirring constantly. Never stop moving that whisk. The mixture will bubble and foam at first, then smooth out. Cook until you reach your target color.
Add liquid gradually while whisking. Pour liquid in small amounts, whisking after each addition. Cold liquid into hot roux works fine—the gradual addition prevents lumps.

Tips & troubleshooting

Keep your liquid warm when adding to roux—cold liquid can seize up a hot roux
If lumps form, strain the finished sauce or use an immersion blender
Darker roux has less thickening power, so you need more of it
Make roux ahead and store covered in the fridge for up to a week
The smell changes as you cook—raw flour becomes toasty, then nutty

Variations

White Roux. Cooked just until the raw flour smell disappears, about 2-3 minutes. Perfect for béchamel and cream sauces.
Blonde Roux. Cooked until light golden, about 5 minutes. Use for velouté sauces and light gravies.
Brown Roux. Cooked until deep brown and nutty, 10-15 minutes. Essential for traditional gumbo and rich gravies.
Oil Roux. Made with neutral oil instead of butter. Handles higher heat and stores longer. Common in Cajun cooking.

Questions

Why did my roux turn lumpy?: Either the flour wasn't mixed in fast enough or liquid was added too quickly. Whisk flour immediately when it hits the fat, and add liquid gradually while whisking.
Can I use different fats besides butter?: Absolutely. Oil works great for higher heat cooking, bacon fat adds flavor to gravies, and even olive oil works for lighter sauces.
How much liquid should I add to roux?: Start with about 1 cup of liquid per 2 tablespoons of roux. Add gradually until you reach the thickness you want—you can always thin it out later.
What if my roux burns?: Toss it and start over. Burned roux tastes bitter and no amount of seasoning fixes that. Lower your heat next time.