use 5.14.1;
use warnings;

format STDOUT_TOP =
@   Size   Price
"#"
@   ----   -----
"#"
.
format STDOUT =
 @>>>>>> @###.##
$a, $b
.

my %pizza = (
    Small  => 12.34,
    Medium => 57.78,
    Large  => 90.12,
    );

while (($a, $b) = each %pizza) {
    write;
    }

=>

#   Size   Price
#   ----   -----
   Small   12.34
  Medium   57.78
   Large   90.12