Pressure Cooker Risotto in 7 Minutes

I actually combined several recipes in one: this one and my usual recipe for Pumpkin and Sage risotto, plus a good measure of my own ideas (I also read this one, specifically including the comments, but decided I'd try this one first).

I think the most important part of this recipe is the question how much stock you need to add in relation to how much rice and other ingredients, and how long and with how much pressure do you need to cook it. This recipe gives a ratio of 1 part rice to 2 parts stock, which you'll cook for 5-6 min on 'high' (I did 6 min). Unfortunately, the resulting risotto was undercooked; I'll make the risotto again and use a ratio of 1:3, and maybe 8 min. That said, using a pressure cooker for risotto is an enormous time saver, especially because you can prep everything up to the moment you add the stock and start the pressure cooking!

According to my usual recipe, 350 g rice should be enough for 4 servings, so 175 g (equals exactly 1 of these plastic cups of 160 ml that come with the Instant Pot and most rice cookers) should be enough for 2 servings. It wasn't (though maybe yes as an appetizer?). It wasn't immediately obvious to me if this 7-min risotto recipe was referring to plastic cups or standard cups, but given that 4 cups of stock are given as an equivalent of 1 litre, it seems to be the latter. ½ standard cup aka 120 ml equates 130 g rice, which should be enough for 1 serving.

I also used defrosted roasted pumpkin – my, it lost a lot of liquid! It went from 370 g both fresh and frozen to 190 g thawed and roasted. I dithered quite a while how the pumpkin would influence the required amount of stock, until I read the whole pumpkin risotto recipe and realized that the pumpkin is only added at the very end, after cooking. Duh!

PS: How very fitting that I reviewed a 'Risotto in 7 min'-recipe on 7/7/17!

Edited a few days later: A rice to stock ratio of 1:3 with 8 min on high resulted in mush! I might try 1:2.5 and 7 min next time, or just stick to 1:2 and 6 min and finish it off the traditional way. Complicating factor was that I used a different rice, though, so may be it was actually the rice?

Edited 5 August 2017: We're getting closer, or not. I made a Tomato and Basil Risotto, using the same rice as the first time, the same rice-liquid-ratio (1:2), and the same amount of pressure cooking time (5 minutes). I planned on getting undercooked risotto, because then I'd be able to put half away to finish cooking tomorrow, and I'd have the chance to add mozzarella during the last few minutes on the stove. Alas, the rice wasn't undercooked.

At first I couldn't make any sense of this, given the different result of the first time; but the one thing that was different was that this time I made a full recipe, with 350 g / 400 ml rice instead of just half of that. So my hypothesis for the time being is that quantity also matters, and is probably also related to the size and make of my pressure cooker (8 litre/quart Instant Pot) (eagle-eyed readers will observe that this time 350 g equals 400 ml and not 320 ml - I used a different measuring cup. No idea if this is simply what you get with measuring cups of different width, or if one of them is plain wrong).

Edited 7 October 2017: 350 g rice, 750 ml stock and some glugs of different wines, 6 minutes - just/nearly cooked.