Chuck roast is also very cost effective and dead simple to make. 8-10h in a slow cooker on low with salt, pepper, and some butter or anything else you want to add and you'll have super high protein meals (~60g of protein in 8oz of cooked roast) for a few days.

@Bill Quistorf Much appreciated!

@Carsten Breum Thanks, I was admittedly "hardcore" or maybe dogmatic when I first tried carnivore. I went full on Lion Diet but that was more about knowing myself and that I do best being all-in or not...half-measures don't stick with me very well. Over time, though, I learned more and kept educating myself and challenging what I thought I knew. I do think the most important change is more about eliminating highly processed foods and refined sugars. I now eat blueberries and some kale or spinach along with avocados a couple of times a week. I am lifting now on week 2 of a 3x-day plan that I kind of cobbled together. Once I prove I'm consistent with that, I will likely look for something better and will check out the options mentioned here for sure.