✓ Warm the liquid first. Always heat up stock, milk, or cream before whisking it into the roux. Adding cold liquid to a hot roux can cause it to seize and break.
✓ Add gradually. Add a little liquid at a time, whisking to incorporate between each addition, until smooth. Same goes when adding the chopped Cajun trinity to the roux for gumbo. Stir in small amounts at a time so the roux doesn’t “shock”.
✓ Warm it up. If using a pre-made roux (homemade or store bought), warm it up before adding it to your dish, but be careful not to darken it further.
✓ Pour off the oil, or don’t. If using a pre-made roux, some oil may separate to the top during storage. You can choose to stir it back in, or discard the oil layer. Removing it won’t change the flavor of the roux.