Is this what you're seeing KB?

"An Error Has Occurred!
The attachments upload directory is not writeable. Your attachment or avatar cannot be saved."

Don't forget the Reverse Base (Onions Baked).
Reverse Base

Although, you could just fry and melt some onions first or use some bought onion paste.  I have used this one, which I found to be pretty good.  You should be able to find a similar product over there.  I believe Shan does one as well.
Sabrini Onion Paste

Well, there is no need to do that Robbo. Rik's paste is just as good and really not difficult considering the yield for effort. You like it so why bother looking elsewhere? I just found the Ashoka in my cupboard, so I tried it.  I won't buy it again.

Very worthwhile trying this one.  It would work with Rik's Onion Base.  To be completely honest, I would not have been able to pick this from Rik's Vindaloo given a blind taste test.  I'll test them out again today after 24 hours to see if they are different.  Obviously, I did a chicken version and included fried potatoes.

Acidity. 2 things. For Rik's paste I used Cornwell's Brown Malt Vinegar and I'd imagine the Ashoka paste probably uses generic strong white vinegar (acetic acid). I don't think it's necessary to measure the pH and it was just my initial observation from a quick taste. The Ashoka had more vinegar tang.

After resting the curries for 3 hours and eating them for dinner (side-by-side on the same plate) I couldn't really tell them apart. Mrs Livo said she thought the Ashoka dish was sweeter and that makes sense as gram for gram it does have more sugar in the finished dish.  I couldn't say I tasted it, nor could I discern the sharper vinegar tang any more.

What do I think of Chicken Vindaloo? I really like it and I was pleasantly surprised that it isn't a stupidly hot chilli dish. It was really nicely balanced and Mrs L didn't mention it being too hot.  I didn't tell her it was vindaloo until after she'd eaten it.  I only made a quarter of the amount of Vindaloo paste using 3 de-seeded and rehydrated kashmiri red chillis and 1 large fresh red Cayenne pepper, also de-seeded. The powdered chilli was as per the recipe scale but I did use mild chilli powder, not hot.

The aroma of vindaloo is strong and enticing. Once the kasoori methi hits the pan you really notice it.

Rik's pastes take a bit of doing but once done the cooking of the dish is so easy and there's a few dishes in it.  Masala Mark's recipe with the Ashoka paste with onion paste (mix Sabrini and bunjarra) used whole spices and pre-cooked chicken but again a quick easy cook as you'd expect for a restaurant style recipe.