My other major tip is beans for breakfast. Lots of protein, fiber, etc. and similar satiated feeling that you get from eggs. I make "refried" beans by cooking dry beans overnight in the crock pot, and then blending with an immersion blender. I keep a big pot of these in the fridge at all times and eat a mug of them every morning for breakfast, with cheese or hot sauce or avocado on top (or with a tortilla). I've never calculated how much this costs but it's pennies every day because I use bulk dry beans. Other tips if you actually do this: Soak the beans for ~8 hours before cooking, this gets rid of the fart factor. I also add 1 shredded onion, cumin, cayenne, garlic, salt, and a shredded hot pepper in the crock pot to add flavor. This thing seriously changed my life- I eat breakfast around 7:30 and sometimes I'm not even hungry for lunch until like 2:30PM.
I also am biased (vegetarian, as previously mentioned) but I second the recommendations to eat more beans in general and vegan proteins. They are definitely cheaper if you are OK with cooking a little, way more sustainable, and I very rarely have to throw away food that went bad/out of food safety concerns because slightly old beans are way less scary than slightly old meat, haha. You can get a 25lb bag of dry beans at Costco for like $15, and that would last even me several months. Daal is great, as is homemade seitan- definitely a weird one, but look into it if you're adventurous; it's cheaper than chicken but has similar protein content and mimics chicken in recipes. My carnivore fiance loves "seitan nuggets" on the grill pan with barbecue sauce.
Yes, this! That was my first thought, too, after reading "$200/month on breakfast/lunch." That's a lot for one person, for only 2 meals a day?! You could really get more bang for your buck. My fiance and I can eat for a whole month for that much, lol. I've been plantbased for 2 years and this is markedly less inexpensive than when I was eating a meat. That's actually one big reason why I explored the idea of a plant-based diet - it's a lot cheaper while still being healthy. You'll have to kind of experiment with what you think tastes good, but a vegetable chili is a good choice for lunch. There's 3-bean salads, if you're into that. I love a good stir fry. Lentils are great and I enjoy making a sort of casual stew/curry by adding tomato sauce/paste and spices. Legumes are a great vehicle for protein and other nutrients. You can add edamame or beans or salads. You can do 'buddha bowls,' where you add some protein of your choice to a bunch of roasted/cooked vegetables, such as sweet potatoes and broccoli. Chickpea or tofu scramble seasoned with some turmeric and salt/soy sauce/liquid aminos is a good alternative for eggs. Tempeh is also great because it's a fermented food, but I know not everyone likes this. However, I really enjoy it sliced and stirfried with a bit of garlic and soy sauce, with vegetables and rice. Just be creative and you know, use the computer as a resource for recipes... lol.
In addition to swapping out protein options, you could incorporate some grains that are higher in protein, such as quinoa, amaranth, bulgar, farro. There's a lot of options. These are all available in the bulk section in most grocery stores. You could also try soba noodles, since buckwheat has a lot of protein. Also, I recommend Banza pasta as an alternative to regular pasta, which is made from chickpeas, so it's higher in protein, if you're needing extra. However, most people overshoot their need for protein anyway, so I'd also focus on eating quality foods in general.
Ditto on the seitan - I've made that and my fiance LOVES that. This is actually a good reminder to make some, actually, since I haven't in a while. This is the recipe. It's super quick and easy. I throw it into a steamer/rice cooker after I complete the steps:
http://www.thatwasvegan.com/2012/01/30/my-favorite-chicken-style-seitan-recipe/By the way, this isn't post isn't to say "go veg!" but just to point out that there are options you can substitute for some of your meals that will help bring the cost down. Even when I was an "omni," I still ate a lot of plant based meals because food is fuel, after all, so quality is really important at every meal. Cut down costs, but don't do it so much that you're just eating crap. I've seen way too many crappy food decisions on those reduced budget threads where all they do is stock up on carbs and processed foods.