I purchased a new crockpot a few years ago. It cooks beans like no bodies business. The previous one took two days. For a few bucks I have plenty of beans for a few days worth of eating. One of my children can eat two cans of beans in a sitting
For sloppy joes we use a mix of red dal and tvp. I used to use the frozen crumbles, but I slowly started to add in the dal and then one day I just went to the tvp. I got no complaints, but I didn't tell anyone.
Make the lentils and provide a few sides. The lentil hater can just eat the "sides". BTW, don't think of dishes as sides. Baked beans are a great main dish.
Stop eating those granola bars. Are they really worth it? I have a really small budget, so for me it just isn't. I would rather buy fruit or have smoothies. My homemade cookies are much better and I can make a bunch for that price. I like this
Eat leftovers for lunch.
Use the crockpot.
Cook in big batches.
Prep food for cooking after or during dinner (or at another meal if that's easier). Chop veggies for 2 or 3 days. Soak a pot of beans. Put out a jar of grains you want to cook. Heck cook extra grains (pasta, rice or potatoes), put them in a large bowl to cool. The next day turn that into a salad for snacks or lunches.
Make a food schedule and menu. If you eat Tacos on Monday, make enough for taco salad on Wednesday. Put the leftovers in small containers. Put all those containers in a crisper drawer or dishpan. Label it KEEP OUT.
Make a giant pot of chili. One night it's served with cornbread. One night it's on potatoes. One night it's enchilada filling. One night it's for chili dogs, chili cheese fries, nachos....we like chili....ymmv.