It’s not really meal prepping in my mind since I can only eat the meat, but I made a little less than a pound of lean ground beef with a taco seasoning packet and I’ve been eating that for the week with fat free shredded cheese. If you are farther out you could do a wrap, taco, veggies, sour cream, etc.
Also you might like the muffin tin recipes on Pinterest. You can search bariatric muffin tin recipes and a lot will come up. A lot are made with wonton wrappers and the “guts” can be Italian, Mexican, breakfast, etc. I like taco cups, meatloaf cups, and lasagna cups best