I bet I could eat an entire box of hamburger helper. I know I could eat three cheezeburgers at a sitting. Once in a rare while I indulge in junk food like that. But beef tenderloin costing maybe $25/lb naturally tends to take care of the whole "technically you only need 2 oz protein per day" or whatever it is exactly.
Yes Chinese restaurants are famous for using interesting (gross) parts of the chicken to increase profits, but for how little chicken I use in a family sized stir fry I can afford a clean probably not salmonella infected boneless skinless organic chicken breast.
I mean, sure, for $10 I could eat hot dogs until I puke and/or gain two pounds of fat, but I'd rather eat a nice small grilled steak.
As a rough guess the more you use your grill and wok and the less you use your oven, toaster, and microwave, the healthier you're probably eating. Also a wok looks expensive as an experiment, like a couple meals worth of food, but unless you do something crazy it never wears out and its cheap compared to something like a complete all-clad stainless steel cooktop set. Also if you're trying to learn how to cook, most vegetables will not kill you with food poisoning no matter how hard you try, so some vegetarian stir fries are a delicious place to start.
This a thousand times. My wife and I cook most of our meals at home and whenever someone asks me how to get started I always recommend a good quality (read $20-30) carbon steel wok that will last for decades if cared for properly. The ease/flexibility of cooking in it is amazing and healthy stir fries are close to idiot proof for beginners so long as they follow a couple of simple rules.
EDIT: the other tip I generally give is learn the base of a vinaigrette (one part vinegar to two/three parts oil) and it will absolutely slash the amount of worthless calories and sugar you consume. When trying to eat healthy so many people will prepare a salad (good) but then drench it in store bought salad dressing without reading the label (bad). With the base recipe you can experiment with different vinegars and acids (e.g. lemon juice) plus flavor boosters like garlic and shallots which will produce a super tasty and healthy dressing at a fraction of the cost of buying something at the store.
Then one day, my wife had prepared salad fixings for dinner and I assembled a bowl with lettuce, tomatoes and cucumber, topped with a small handful of peanuts and sesame seeds and a little cheese... not a bad meal, but I needed a little dressing. I enjoy dressing as much as the next guy, but I do try to use as little as possible.
Anyway, the lettuce was pretty wet and I had a flash of insight... I just sprinkled the ranch dressing powder directly on the salad and it worked great. You get the tang and savor, without all the fat and sugar.
Eating healthy, cheap, easy is easy if you put even 4 hours of thought into it and are willing to learn. I'm in Toronto Canada, so these might not be tailored to you, but you can get the general idea.
1. Eat things in season. Squash, carrots, onions, sweet potatoes, corn are just unbelievably cheap in the autumn. Use garlic, onion, bay leaf, oil, a couple thai chili peppers fry them in the bottom of a pot with some coconut oil. Put the cubed squash (skins and all!) in the pot with a lid and some stock (veggie or chicken) until soft. Smush down add other veggies and add a half can of coconut milk and you have 8 or 10 meals at around a $1 CAD per meal. Easy to heat up, bring to work, lasts a while in the fridge.
2. Eat better, cheaper animal protein. Mussels are very cheap and very delicious. Canned clams are easy too. Sardines on toast are easy and delicious. Eggs. If you're adventurous get the butcher to grind beef heart with chuck and make much healthier beef heart burgers.
3. Figure out the cost of things per calorie, but be careful to restrict what you buy to just within the set of healthy foods. For example, whole milk is pretty cheap per calorie and still pretty healthy if you're of European ancestry. Nuts look completely overpriced until you realize that they are 1/5th the cost per calorie of carrots. I know it seems counter intuitive to try to find calorie rich foods, but if you're poor you do need to pay attention to this. Avocados, olive oil, granola, almond butter.
4. If it is dry, canned, or otherwise keeps, buy in bulk. Brown rice, steel cut oats, flour, cans of tomatoes, bags of onions, carrots, everything.
5. Slow cookers make things easy, pressure cookers make things fast. I own one that does both and if you want fast, healthy, cheap, delicious: one chicken leg, some stock, veggies, some dry spices + pressure cooker = perfect meal in 10 mins with very little cleanup.