@SteveJB @TheBreadmonkey @julianlawson Right, I'm going to have to crave Ben's pardon for a Bad Photo of Food. I'm not really a weights and measures sort of cook, but I tried to eyeball the quantities so I could post them for posterity.
I started with a tin of beans. The Tesco reduced sugar and salt variety as it happens, but any beans will do and I immediately remedied Tesco's omission. The sauce is very thin, so I started by adding a good squirt of tomato puree to thicken it up.
Then I fried up maybe 1-1.5 teaspoons of mustard seeds in some leftover bacon grease that was sitting in the frying pan since breakfast, which fortuitously added a hint of pork flavour when I poured it in. If you don't have bacon grease to hand or consume animal products in general you can just toast them dry in the saucepan until they pop before pouring in the beans.
A good skoosh of red wine vinegar. Maybe a tablespoon and a bit. About a tablespoon of lazy garlic, which I noticed also comes in wine vinegar, so I had to add a teaspoon of Muscovado sugar to balance it out a bit.
Then I added:
0.5 tbsp ground ginger
1 tsp ground coriander
1 tsp ground cumin
0.5 tsp turmeric
0.25 tsp salt
And about a tablespoon of ground cayenne pepper. Feel free to adjust this to taste, it's not essential that a vindaloo be face melting. Authentically it's more medium hot, I'm just a lunatic who eats weapons-grade peppers so a bit of cayenne is a pleasant kick.
I let it simmer in the pan for a bit to let the beans absorb the unfamiliar flavours, and vindabeans were achieved. Hot, sour and delicious.
Verdict: not fucking bad for a first effort.