The variety of gnocchi in the world is as large as my childhood coin collection. Yes, I was that kid. I collected coins and soft drink cans/bottles. The latter grew quite big as well before my mother told me to get rid of them as they filled up too many of my shelves. I also collected model cars, but they were expensive as I only got them from proper Ferrari stores and such so that wasn't enough to call it a collection. Anyway, I digress, back to gnocchi. There are those made with potatoes, flour and egg; potatoes, semolina and egg; semolina and flour; potatoes and flour; those made with a choux base; those that include spinach or squid ink; those made with ricotta etc etc.
I had never made potato gnocchi (ie just potatoes and flour) until two days ago. Sources suggest that omitting the egg makes for fluffier gnocchi. However, I have to say that the fluffiest and lightest gnocchi I've ever had were those made with a choux base. That was at my favorite restaurant in Edinburgh, The Kitchn, and oh I believe they were served with some sort of seafood. I can't remember exactly, I have the picture of it somewhere on my phone. I take photos of everything I eat -- yes, I'm that Asian girl. However, as much as I loved those gnocchi, choux-based gnocchi are French and since I'm in Italian I felt like I had to master my own country's version before I experiment with the rest. As I was saying, I had never made potato gnocchi before, though I'd seen it made on TV dozens of times, and they all just say "add flour until it feels right". So it was a bit daunting as I didn't know what "right" felt like. Be wary of recipes requiring only two ingredients because those are the most difficult ones. Everything needs to be perfect, and so I did my little research.
Use a "halfway" potato that's neither too waxy or too starchy, most British recipes suggest Desiree. Boil it and then dry it out in the oven at a low temperature so the gnocchi are even fluffier. After it's dried, pushing it through a sieve would be the best idea as it would add more volume. A potato ricer works too. Then you wait for it to completely cool down before kneading it with flour.
Most Italian recipes ask for strong flour, but I see a lot of British recipes not mentioning it so I suppose it doesn't matter too much.
Ah. Use as little flour as possible I think. I've seen the potato flour to be anywhere from 10:4 to 30:5 and I think I did something like 400g of potatoes to 100g of flour. Oh and make sure to add a pinch of salt.
Kneading and cooking
Work the dough as little as possible, just until it comes together, and don't add all the flour at once. Afterwards, roll into a log and cut into bite size pieces. Roll each along a fork to form that classic pattern if you so desire. Bring a pot of salted water to the boil and throw the gnocchi in there - don't overcrowd the pot, do this in batches. When they begin to float on top they're ready - this just takes 1-2 minutes. Then count to ten and take them out with a slotted spoon. At this point you can either fry them in a bit of flavored butter and cheese or throw them in a pot of sauce.