I know I had coffee gelatine as a kid. Either it was something someone concocted or it was another brand. I thought it was pretty good.
Does anyone remember peanut butter with bacon bits? This was mid-60s. I think it was Skippy. As a kid I hated it, but the rest of the family loved it. Then it disappeared.
How about Shake-a-Pudding? Instant pudding mix in a cup that you add milk to and shake. It didn’t take many of those sprayed around the classroom for them to be banned at school lunch.