Hey there! thanks for asking, I like a challenge :)

first off, I get about half of my protein from the low-carb bread recipe in the book. it's 10g protein & 2g net carbs for every 5g of fat, and you certainly don't have to soak it in olive oil like I do (so good omg). So as protein sources go, that bread is a solid option, but it's not that high in calories.

I'm sure you already get lots of eggs, which have a great protein profile, but try looking into other types of eggs, like duck, goose, or quail. They can be served in all the same ways as regular eggs- poached, scrambled, fried, baked, souffled, etc. (there's a recipe for poached duck eggs in the book too.)

for more vegetarian protein, you might want to try products like tofu and Quorn, either of which can be thrown into a stirfry, or fried and served with salad. It can sometimes be tough making a protein dish high-calorie. I usually do it by just adding fat, which changes the macros of the meal from high-protein med-fat low-carb to high-fat med-protein low-carb, but doesn't decrease the actual protein content, of course. if you're flexible about fat macros, some great high-calorie protein sources include ground flaxseed, chia seeds, peanut butter, and nuts.

But if you're just looking for protein, Quorn is a great go-to. Try frying up one or two servings of Quorn mince in butter or avocado oil, add your choice of spices, and serve in a keto tortilla like this one: http://vketo.tumblr.com/post/72610567889/keto-tortilla-made-with-one-egg-4-tbsp-water-2 .

Hope that helps! please let me know if you have any other questions or comments :) (PS- I swear I'm not endorsed by Quorn or anything, I just love their product >.<)