Combine stock with roux.

Combine stock with roux.

• A. Slowly whisk hot stock into the roux to avoid lumps, then simmer to the desired thickness.
• B. Add all stock at once and boil vigorously.
• C. Whisk cold stock into roux vigorously.
• D. Use plain water instead of stock.

Answer: (A)

The technique here is smooth thickening through gradual, temperature-controlled incorporation of liquid into a hot roux. When you slowly whisk hot stock into the roux, the starch in the flour hydrates evenly and emulsifies with the liquid, preventing lumps and giving a smooth, cohesive sauce. After the stock is added, bring it to a simmer so the starch can swell fully and the sauce thickens to the desired consistency. Adding all the stock at once or using cold stock invites lumps or uneven thickening, and using plain water would dilute flavor and body.

The technique here is smooth thickening through gradual, temperature-controlled incorporation of liquid into a hot roux. When you slowly whisk hot stock into the roux, the starch in the flour hydrates evenly and emulsifies with the liquid, preventing lumps and giving a smooth, cohesive sauce. After the stock is added, bring it to a simmer so the starch can swell fully and the sauce thickens to the desired consistency. Adding all the stock at once or using cold stock invites lumps or uneven thickening, and using plain water would dilute flavor and body.