I have no idea about food prices in your part of the world, but being a high school student living on a very small budget (think $200/month for food expenses, and this is Denmark which is relatively expensive) I have learnt a few tricks.
One of them is baking your own bread! I have an electric mixer with some special tools for dough, so I spend 15 minutes every two days and have pretty good and cheap bread.
Soups are another nice one, forget about the advanced ones, go with something simple, yet good, e.g. potato-leek-soup. Make big portions, put it in the freezer.
Basic courses such as pasta can be pretty good if you spice it up a little. Forget about the ketchup, mix up a simple tomato sauce.
And a little gem from The Silver Spoon: Some oil on a pan, put on a whole garlic clove untill it's brown, get it off the pan. Add a can of tuna, and some tomato puree that has been mixed with a bit of water. Turn down the heat, give it some fifteen minutes and add to your pasta. Inexpensive, easy and surprisingly good if you spice it up a bit.
Basically anything that you can make in big portions and freeze is a bargain.
+1 for your own bread. My mother gave me a recipe for "food processor" bread, which involves about $0.25 worth of ingredients and a few minutes of work.
It's not the right season at the moment, but you could also consider growing your own stuff in the garden. Fresh herbs from the grocers are $$$, and don't taste/smell as good as what you pull and carry to your stove.
Commercial tomatoes breeds are optimized to have a tough skin, so that they can be thrown into large containers while green and hauled to the grocery store while ripening. None of this has anything to do with tasty or healthy. Growing your own tomatoes is also easy if you have a sunny spot, and you can pick varieties that taste better than what you'll end up with from the store.
None of these are cost-optimizing in a large way, but if you're going to be cooking anyway, you might as well enjoy better taste and the satisfaction of producing something physical and tangible.
Although I have the acreage to grow pretty much whatever I want, you can grow lots of stuff in a small apartment as long as you have a window that gets enough light. Herbs don't take up much room, esp. if you use a strawberry pot and plant multiple types in the same pot. You can also grow tomatoes, etc. in pots
I'm a undergrad student in Finland and trying to manage relatively cheap aswell.
I try to live by low-carb, high protein, high natural fat and fresh and natural foods, which atleast doesn't make it any easier. I have found out that most fatty foods are inexpensive relatively to their calories. Where as things like bread are actually quite expensive if you measure their calorie contents and other nutrients.
So my advice is to eat more natural fat, even to point that you get like 30% daily calories from fat. Generally I try to choose products with high or normal fat. For example full milk over fat-free and unsweetened Turkish yogurt(with 10% fat) over fat-free and high-sugar.
One of them is baking your own bread! I have an electric mixer with some special tools for dough, so I spend 15 minutes every two days and have pretty good and cheap bread.
Soups are another nice one, forget about the advanced ones, go with something simple, yet good, e.g. potato-leek-soup. Make big portions, put it in the freezer.
Basic courses such as pasta can be pretty good if you spice it up a little. Forget about the ketchup, mix up a simple tomato sauce.
And a little gem from The Silver Spoon: Some oil on a pan, put on a whole garlic clove untill it's brown, get it off the pan. Add a can of tuna, and some tomato puree that has been mixed with a bit of water. Turn down the heat, give it some fifteen minutes and add to your pasta. Inexpensive, easy and surprisingly good if you spice it up a bit.
Basically anything that you can make in big portions and freeze is a bargain.