You can’t delete a variant from the Portal, but there are two ways you can remove it from your menu.
Make a Variant Inactive
In the sidebar, click “Menu Management,” then “Variants.” Click the toggle to change the variant from “active” to “inactive.”
Remove a Variant from a Product
In the sidebar, click “Menu Management,” then “Products.” Click on the product where you want to remove the variant.
Click on the variant drop-down and then on “Edit Variants.”
Beside the variant you want to delete, click the circle with the dash in the middle.
Ensure to save your changes.