This is a recipe I grew up with, which my mother learned while she lived in Turkey. For the longest time, I didn't know zucchinis were like cucumbers, because my mom would call this "preparing zucchinis".
Turkish Zucchini galettes
1/4 small onion
4 tbs flour
salt & pepper
Feta cheese (opt, to taste)
Put veggies and egg in a blender and puree until smooth. Add flour, one spoonful at a time, and adjust for consistency of batter.
Because no two zucchinis are alike, this recipe is difficult to quantify. This means you should take the measurements above with a grain of salt (hee). I put the flour measurement here after testing it out for myself because my mom wouldn't even give me a ballpark figure. Basically, if you've ever made pancakes or crêpes, you know what consistency you should be aiming for.
Also, do not put a lot of onion in there. Its flavour is powerful, you don't want it overwhelming the zucchini.
Oil a pan on medium-high heat and pour the batter in little circles - inch and a half does well - then flip when done on one side. Place the cooked crêpes onto paper towels to absorb excess oil. You'll be putting new oil in the pan at every batch, so fair warning.
This step is when you can test your consistency best. If the batter flows too much on pouring or while cooking, add flour to the mix. If it doesn't flatten enough, add more zucchini (or maybe just water). This is why it's best to start with less flour and add it gradually until you get that perfect consistency.
Salt and serve. Best hot to warm, but can also be eaten cold. Leftovers keep in the fridge and can be nuked: just make sure you do it by short periods of time (15-30 seconds, then check) or else you'll end up with thin hockey pucks.
As a personal note, I've never had them with Feta. Mom doesn't think it adds anything to the recipe and I've just made them myself for the first time. They were a hit with my whole family.
Mom will sometimes make large batches by oiling cookie sheets, serving the dollups of batter in rows on them and baking them in the oven, turning when done on one side.