What action is necessary before serving a dish to a guest with dietary restrictions?

Checking the ingredients with the kitchen is essential before serving a dish to a guest with dietary restrictions because it ensures that the food does not contain any allergens or ingredients that might trigger a negative reaction in the guest. This step involves verifying the specific components of the dish to confirm that it is safe for the guest to consume, taking into consideration their dietary needs, whether they are due to allergies, intolerances, or preferences such as vegetarianism or veganism.

Consulting the guest for approval is important but comes after you have ensured the dish is safe based on its ingredients. Cooking the food separately may be necessary in some cases, but it does not directly address whether the dish itself is safe based on its components. Serving the dish as it is would pose a risk to the guest if it contains ingredients that they cannot consume. Thus, verifying ingredient safety with the kitchen is the foundational action to protect the guest's health and provide excellent service.