Growing protein

I follow a few YouTube gardeners for inspiration and knowledge. One of the ones I like is Mark from Self Sufficient Me. He's just completed a three week trial of subsisting solely on food he has produced himself (other than coffee beans, oils, salt, and some condiments). He has a good-sized property and - in addition to loads of raised beds and fruit trees/bushes - has quite a few chickens, ducks and quail that are kept for both meat and eggs. However, it is Winter there (Australia), so they were getting fewer eggs than at other times of year and didn't want to eat any of their birds outside of breeding season. He and his wife ended up with serious protein cravings!

This all got me to thinking about how we can increase our homegrown protein stocks. I'm hoping to get to a point where I'm growing a large proportion of my fruit and veg (as opposed to now, where the things I grow are more of a tasty supplement to what I buy). I'd also like to have some poultry once I have my own garden, but just for eggs as I'm a vegetarian. I'll still be buying proteins in the form of dairy, nutritional yeast, pulses, nuts and seeds. However, it would be really nice to be able to grow a decent amount of protein in my own garden too and I wondered if anyone had any good thoughts about the best crops to maximise high protein garden crops. 

So far, I have been thinking about:

1. Peas and beans - some for eating fresh, some for freezing, and lots to dry. I've only eaten homegrown ones fresh before. Anyone have any favourite options for drying?
   
2. Seeds - I've thought about sunflowers, pumpkin/other squash seeds, and poppy seeds. What other edible seeds can we produce in our gardens?
   
3. Seeds as grains - for example, quinoa and amaranth which are both supposed to be relatively easy to grow (though in significant quantities?) Are there any others?
   
4. Nuts - chestnut and walnut trees are huge, but hazelnuts/cobnuts would go well in a hedgerow. Anyone have experience with growing nut-trees?
   
5. Underground things - I'm thinking peanuts and tiger nuts. Can peanuts be grown in the UK? Has anyone managed to grow tiger nuts in decent quantities?
   
6. Fungi - definitely something I want to try when I have a longer-term garden. Has anyone had good success with inoculating wood mulch or using dowels?
   
7. Other high protein fruit and veg. As a vegetarian, I have often seen lists of these, but you often have to eat a ridiculous quantity to get a decent amount of protein. Anyone have any favourites?
   

I'm not expecting to be able to get close to producing all my protein in my future garden, but it would be great to hear everybody else's ideas about how to produce as much as possible.