My neighbor gave me this plant and this is what the peppers look like. I tried one of his big green ones that wasn't ripe and it was pretty hot where the seeds were towards the core of the pepper.
It looks like a mushroom pepper which I've found to have many different names. I have this same plant in my garden and I got it as a Red Mushroom Pepper. I've heard Balloon Pepper & bishops Crown also. There are some others. I'd like an answer to this question myself. Here's mine: