I don't really skimp on food. I try to by the best quality I can afford. But I do stay away from pre-packaged and convenience foods that cost more.
For example, my family loves hummus. I buy the dried chickpeas . I soak overnight, then boil them with a little baking soda. Two cups of chickpeas, some tahiti, garlic and lemon juice goes a long way for a little money.
I also make lots of stir fries that require little meat and lots of vegetables.