In addition to batch cooking on the weekend, I brown my ground beef (all of it) as soon as I get home from the grocery store. We don't eat many hamburgers. It saves time because it cooks more quickly because it's not frozen and is ready when I need it later that week: shepherd's pie, chilli, etc.
I like to use my Sundays to make meals for the rest of the week. I chop my veggies and put them in plastic storage bowls for my lunches. I cook one thing in the slow cooker to eat on all week. I portion it out for my meals so I never over eat it.
I'm most likely to make an unhealthy meal choice when I'm rushed or tired. To avoid this I set aside time to cook in large batches. Then I freeze meals in individual portion sizes. When I don't have time to make lunch or I'm too tired to cook dinner, I just pull something out of the freezer.