I think it was the roast beef, pre packed from Asda not sure the content of it now as I have not eaten it since. But funnily enough since I have not had the roast beef topside, my levels have started to stabilise again. I have also started to have my last main meal at 3:00pm and that seems to be helping. The chicken I have been okay with as well as fish. All this is making me hungry now!
it would be interesting to know whether something like steak has the same effect as the topside, which probably has other ingredients (they tend to soak meats for cold cuts in a brine including dextrose and salt and heaven knows what else).
But you may find this article about the Insulin Index interesting. The insulin response to beef is much higher than that of chicken.

Insulin Index
Reader Pete asked for some thoughts on the “Insulin Index,” a measurement chart similar to the glycemic index. While the glycemic index calculates the
and you are perfectly right. We are, indeed, all different, so please don’t let anybody tell you that you are ‘wrong’ when you have your own meter giving you clear evidence.
As for pea protein, yes, I have tried it. Got on much better with it than ordinary whey protein.
However, I found that whey isolate was even better - though also significantly more expensive.
I have also used hemp protein, which I loved. That was years ago. Holland and Barratt were stocking it back then. No idea if they still do.