UILabel Character spacing to include background and underline attributes

Question

I am wanting a UILabel where each character is underlined and has a background, while also having a space between the background of each individual character - so essentially each character is in it's own "box"

I have tried using attributedText on a UILabel but having set the NSBackgroundColorAttributeName and NSKernAttributeName the background fills the entire label, essentially I'd like a gap of clear color between each letter.

Is there a way of doing this with attributed text, or will this need to be resolved with another solution?

I currently have tried the following as an example:

NSMutableAttributedString* string = [[NSMutableAttributedString alloc] initWithString:@"EXAMPLE"];
[string addAttribute:NSBackgroundColorAttributeName value:[UIColor whiteColor] range:NSMakeRange(0, string.length)]
[string addAttribute:NSForegroundColorAttributeName value:[UIColor blackColor] range:NSMakeRange(0, string.length)]
[string addAttribute:NSKernAttributeName value:@(5) range:NSMakeRange(0, [string length])];
[label setAttributedText:string];

Current result:

Desired Result:

(you can ignore the colors, this is just an example)