The phrase "sweet bell" refers to someone or something that is delightful or pleasing, just like the sound of a bell that is sweet and pleasant to the ears. Full definition
To keep your furry friend safe from serious gastrointestinal problems, stick with sweet bell peppers. (petconsider.com)
Today, before breakfast, I decide to mix it up with a mini yellow sweet bell pepper. (bonappetit.com)
There's no reason why you shouldn't add some extra veggies to this wrap — perhaps some sliced sweet bell peppers or red onion, for instance. (thespruce.com)