I made yellow pea and aubergine stew. Last time I made it the yellow peas were really tough, so this time I soaked them for around 12 hours. They’re less tough than last time but still tough.
Is that just how yellow peas are? Or is it that I need to cook them differently?
Adding baking soda helps breaks down cell walls, which will help soften the beans.
You do not want to add anything acidic until the end of cooking. That will make them tougher.
This isn’t just for beans though, a small amount of baking soda will make your onion confit cook faster and be darker. A little acid will keep your raw onions crunchy and bright in salsa.
So I add it to the soaking water only? Do I need to boil the yellow peas in water for a bit before adding them to the tomatoes?
Add the baking soda to the soaking water. If you are cooking your legumes and tomatoes (which are acidic) together the legumes will be tougher.
Cook the beans, peas, etc. Then add tomatoes and whatever other acidic ingredients you may be using.
Another source of tough legumes is if they are old, especially if they have been stored in a hot and humid place.
There is a very good Serious Eats article (archive link) Here
Edit: here are their suggestions, for anyone not wishing to read the article