There are several squash type hot pepper sold under proper names. Many are listed as "mushroom" peppers, True leaf has a number of these. Here is one listed as a squash pepper. Ralph Thompson's Squash | Buy Organic Pepper Seed | Seed Savers Exchange

This one that I have grown, Jamaican Yellow Mushroom.

Never heard of these. I gather they are called squash peppers because they have a pattypan shape. I guess it's the deep ribbing? Many peppers have ribs, but maybe not as deep as these?

What kind of squash pepepr are you looking for? As farmerdill gave link and pic to, there's a few different kinds. Some of them can be sweet to getting hot. Some of them have the squash or mushroom shapes, but aren't called squash or mushroom.

Cheese peppers have that same shape. Hungarian Cheese, Tennesee Cheese, Piros Hybrid (one that I grew years ago but looks to not be available anymore)...

Rodney

The mushroom description rang a bell and I googled photos. The ones I grew sort of had a mushroom shape. Came across Tomato Growers and found Jamacian Red and Yellow, and Yellow Mushroom. Ordered those along with some others so thought I would just try what I could that even looks similiar. I think Pepper Gal offered the squash peppers but think she is out of business. Are there many people who sell peppers anymore other than big growers? Thanks.......

Judith

Just be careful who you buy from. My experience hasn't been great with odd seed people.

I'll second avoiding unfamiliar sellers on sites like Amazon, etsy & eBay. No guarantee you'll get what's being advertised.

Tomato Growers Supply (tomatogrowers.com) is a well established company. I've bought from them for years.

There seems to be a ton of small sellers. Or at least it seems like there are more than there used to be. A lot of hot pepper specialized. I wandered down the rabbit hole of hot peppers last fall, hehe. It was fun. I tend to the bigger growers, like Baker Creek, Pinetree, Botanical Interests, Johnnys, a few others. I tend to skip Burpee, Gurnee, Park, Tradewinds, and a few others.