Disclaimer - it is not an actual Instant Pot - just a Pressure King Pro, and even then, only a 3L, but I assume can be scaled up for bigger familes. This did a nice sized one for two people.
I am vegetarian, so used one bag of Quorn mince, and the PKP does not have an actual saute function, so I just warmed it for a little, with a bit of watr added... Obviously it does not need to be browned in the same was as actual minced beef.
After I had done that, I took it out and stirred in a bowl with a full jar of Dolmio Lasagne sauce, put half of itback in the pot (put half a cup o water in first), then a layer of kale because I didn't have any spinach, then some Ricotta cheese dotted on and topped with lasagne sheets broken up to fit across the top, as close to the dges as I could (biggish pieces), then the rest of the Quorn and suace mix, more kale/spinach, Ricotta and another layer of the pasta sheet pieces, and another half cup of water.
I set it for 12 minutes, and there is only one level of pressure setting, so it's all medium. I wasn't in to do a quick release, so just crossed my fingers when I got back in and it had released naturally. All OK, and then I covered it in Mozarella and just put he lid back on (no setting and valve open) for two minutes for it to melt.
The baking tins that are usually suggested (20cm) to contain everything, don't fit mine, so I just did it without anything to contain, and took care to get it out with spatula and spoon. Not too messy - and absolutely delicious (although it may well have been the actual branded sauce, so I will not take all credit) - but it literally only took me 5 minutes to put everything in ---- so easy!