Since I'm a vegetarian, I don't eat fish or shellfish whether during a fast or not. During fasting periods, basically I eat a vegan diet. If you're not Orthodox, fasting typically refers to refraining from all meat, dairy, eggs, and usually fish, wine and olive oil (some consider these to mean all alcohol and oils). Shellfish is permitted. Actual observance is personal, depends on one's one spiritual journey, and should be undertaken with consultation from one's priest. Fasting is accompanied with prayer, almsgiving and confession. I freely admit that the spiritual aspects of fasting pose a greater challenge for me than the physical discipline, but if I'm slack on the physical discipline, of course that makes the spiritual discipline that much harder. Being unprepared, busy, tired, sick, etc., can be a obstacle to observing the fast, so having some easy fall-back recipes is really useful. If you are a recent convert, you may not have built a list of reliable stand-bys, and if you're not, it can be nice to add new ones to the rotation.
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For most of my life my mom made popcorn at 9 pm as a bedtime snack. I grew up eating popcorn made on the stove top, so I don't really like the microwave kind, and in fact, we don't currently have a microwave. Stove top popcorn is very easy to do. I pour enough canola oil into a sauce pan to give the bottom a good coat, then I cover the bottom of the pan with a single layer of popcorn kernels. I put the lid on the pan, leave it vented, and turn the heat to medium high. After a few minutes the popcorn will start to pop. When the rapid fire popping dies down, I pour it into bowls. We salt it, and I like to add nutritional yeast. Mom never buttered the 9 o'clock popcorn, so to me there isn't anything missing, but of course you could add margarine (hopefully a non-hydrogenated one) if you really wanted. Or you could go the other direction and make this a totally oil-free meal with an air-popper.
We don't really have a smoothie recipe. Basically we toss whatever frozen fruit we're in the mood for into the blender, add enough juice to cover the fruit, and blend. This time I think we had mango, pineapple and strawberries. We meant to blend that with orange juice, but we didn't realize we had run out, so we used grape. Not our favorite smoothie ever, but still tasty. This simple meal is surprisingly satisfying, and it's very easy to always keep the ingredients on hand. I have a feeling it would go over well with kids, too. Watch for actual recipes on upcoming Fast Food Fridays.