A roux is just butter and flour cooked together until it smells like your grandma’s kitchen. Melt two tablespoons of butter, whisk in two tablespoons of flour, and cook for a minute. Then slowly pour in some of your soup liquid, whisking until it’s thick.
Pour this back into the main pot. You now have buttery, smooth thickness that makes you feel like a chef. Watch out for that urge to say “roux” in a French accent—it’s a slippery slope to berets.
3 Simple Ways to Thicken Potato Soup - wikiHow
