This I have seen many times (though considered uncommon) before. Some call them “ conjoined” , “ fascinated” or “Siamese” tomatoes. It has something to do with the growing tip going in the wrong direction. Hank, most likely Bamboo would know all about this phenomenon.

Thanks L, after sending the post I realised “conjoined” was the word I wanted, but I’d not heard the others - although they do make sense.

I have seen this quite a lot. I think you will find it's an unstable gene or sometimes a virus. There is a term Catfacing and Sunscald can also lead to deformed fruits. Temperature and poor pollination a possibility.

we get some like this every year and some that look very 'suggestive' much to my daughter's delight when they were younger. it is a 'mistake' during cell division and where cells that should have separated completely into different regions don't so both 'germ' cells start growing properly. Conjoined is the accepted term now for this event.

I had one back in the summer Hank. Posted on here but with a face.

Sometimes 2 tomatoes will meld into 1 if they don't have enough space to develop normally. It sometimes happens with 3 or more and you get a huge contorted mass of goodness. I would just add a slice to a grilled cheese sandwich and call it a day.

V Ery interesting guys. Thanks for your comments