You may be able to request modifications to a dish's ingredients and preparation. Select your item and use the 'Special Instructions' field to include instructions or requests for having a dish prepared.
NOTE: For allergy needs, put the request in the allergy field instead of including it in the special instructions. The merchant may be more likely to accommodate the request if it's added to the allergy field.
To find allergy friendly restaurants and add allergy requests to an order, follow the instructions in the articles below.