What are some frugal snacks to have in the house?

Hello Frugal! Long time lurker, first time poster. I was wondering if you could provide ideas for some affordable yet delicious snacks to keep in the house. Since the pandemic started, we have not been eating out and have been home much more like many people. We find ourselves wanting to munch a lot, but so many store bought, pre-made snacks are so expensive compared to how much you get.

We have adapted to popcorn on the stove top which is probably the cheapest snack we have, but we eat it on almost a daily basis so I am getting a little burnt out on it. I've found that I enjoy munching on produce like cucumber and celery, but other than those I am having a hard time thinking of things that are affordable.

I am drawn sometimes to more unhealthy options like chips, but they don't make me feel good so I try to avoid them. I think my munching stems from when I was a kid as my parents have always had munching food in the house. I am hoping the true frugality won't lie in completely omitting all snacks because I truly enjoy them, however in excess I do understand that it is an expensive and a potentially unhealthy habit.

Thank you for any suggestions you have. We don't have children or anything yet but I'll munch on almost anything.