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.