A burger is never just a burger. It is a size, a side, extra cheese and “no onions, please”. If your online menu can’t ask, the phone rings instead.
WP EasyCart builds the menu the way your kitchen thinks. Under Products › Option Sets, make a set once, say Size with Small, Regular and Large, and give each choice its own price. Paste a list takes one choice per line. Then attach the set to every dish that needs it, or press Assign to products to do a whole range at once.

Pick it. Price it. Plate it.
Extras are modifiers. A Checkbox group offers paid add-ons like bacon, avocado or a second patty. A Radio group asks fries or salad. A Text area takes the special request. The price updates as the customer picks, and Shopper must choose before adding to cart makes sure nobody forgets the side.
Modifiers never touch stock, and there is no limit on how many a dish can have. Change the price of extra cheese in one set and every burger that uses it follows.
Pair it with restaurant pickup and the same order arrives with its extras and an “ASAP or 6:30?” pickup time. Your menu, your website, no marketplace commission.
Where: WP Admin › EasyCart › Products › Option Sets, and each product’s Options & Variants tab. Plan: the free plugin covers sizes with Dropdown and Swatch sets; modifiers for extras need PRO or Premium. Read the options guide.
WP EasyCart PRO
Put the whole menu online. Extras included.
Menu, extras, pickup times, payments and receipts in one plugin. The free trial unlocks PRO on your own site. Rated 4.5 out of 5 by 200+ store owners on wordpress.org.