Marilyn, a quick and easy go to (especially if you are looking for protein + fat) is hard boiled eggs. You can also work up some quality points by buying your eggs patured/pasture raised. Another one that takes a little bit more time and effort is homemade beef jerky. I like this option because it is very lean in the case that you've already eaten plenty of fat. I like to marinate it in coconut aminos (a soy sauce replacement), a little fruit juice (negligible sugar if you just marinate the meat with it as long as you get good quality), and spices like chipotle powder, smoked paprika, salt, etc. I'll marinate overnight, then use my dehydrator. An oven on the lowest temp possible will do the same.