I don't have a specific recipe, but I do have a few tricks and tips.
Ingredients:
leftover mashed potato @ room temperature
egg (room temperature)
plain flour (all-purpose)
salt.
It's best if the mashed potato isn't too sloppy and was mashed rather than pureed. Pureeing potato gives it a texture like glue and is too smooth. Tiny lumps of potato are not a problem.
Quantity - do small amounts at a time and never make the dough ahead.
For one cup of mash, add one large egg and half teaspoon of salt. Mix with fork until it's evenly mixed, then slowly add flour. At a certain point it will start to crumble - you don't want it to get to that stage. It needs to still hold together but be getting a bit stiff. Still very moist.
Now for another tip - don't keep working the dough, just sprinkle on some more flour. Also spread some flour on your work bench.
With a spatula, 'slice' a chunk of the dough and drop it onto the floured bench. Roll the dough carefully to coat it with the flour and keep rolling until it forms a snake (like making your first ever clay sculpture in pre-school). The snake should be about as thick as your forefinger. If the snake is sticky, sprinkle it with more flour. It should be coated with flour, rather than have the extra flour worked through.
Next - cut your snake into short segments about half an inch long. Gently toss those segments into the flour to coat the cut surfaces.
Then getting your fork, gently press the segments to flatten them, and then gently roll them off the fork with your fingers, letting them curl a little. Put them on a plastic foam tray (it's non-stick) or a floured plate.
Make more until all the dough is used.
The foam trays I use are ones we get from greengrocers with vegetables packed on them sometimes. I find they are great for this job.
When you've made all the dough, or if you have a second person helping, put some salted water on to boil. Have a slotted spoon ready, and a bowl. When the water is at a rolling boil, drop in a tray full of gnocchi. I give the pot a couple of gentle stirs to swirl the water and stop them from sticking to each other. They should sink at first but as they cook they rise to the surface. After they've been on the surface for about half a minute, scoop them out with the slotted spoon and put them in a bowl. Don't leave them for more than a couple of minutes, without adding some sort of sauce or they will all stick together.
Sauce options - butter, pesto, Napolitan (tomato-based), bolognese.
Once a few have been cooked, the water is at more risk of boiling over. Have a cup of cold water handy to throw in to cool it off a little and avoid a boil-over. Throwing in another lot of gnocchi to cook also cools it enough to prevent a boil-over for a few minutes.
I find that by beginning to work the dough by coating it with flour while still sticky, instead of kneading it into a dough, makes them far less gluggy and doughy. Less like cannonballs, much lighter.
Also, they are traditionally squished with a fork to flatten them - it also makes them curl a little as well as put grooves on the surface, which not only holds the sauce well but also helps them cook through better and not taste so floury and doughy.
Gnocchi takes a little practice but is well worth the trouble. I learned how to NOT do it by making a lot of mistakes myself. I used to make a large batch of gnocchi dough and put it in the fridge - it would go grey and watery, which meant I had to add more flour to it, which meant it was like chewy lumps of glue instead of tasty light morsels.
The flavour is better with less flour too, because there is more egg and more potato.
A small batch can be put together in the time it takes the water to boil. I have sometimes made up a number of trays ahead of time before boiling it, but if I need to make a lot, I make and cook it in small batches and put it, cooked, into a buttered or sauced dish and then reheat it later.
A recipe I've done for the family - I'll half-fill a casserole dish with a mix of gnocchi and bolognese sauce, then cover it with a cheesy bechamel and bake it in the oven.
Gnocchi is nourishing (protein from the egg, carbs from the flour and potato) and great comfort food and filler especially in winter. I've made it on holidays. It's also very cheap to make but doesn't have to taste cheap. If you buy it ready-made it's nowhere as nice and costs a lot more than other pre-prepared pasta dishes.
Making gnocchi is really good to do with kids. difficult child 3's Occupational Therapist said that making gnocchi was really good for his hypermobile joints - rolling the snake, then cutting it and squishing with the back of the fork - all good for his finger joints. It's a really good thing to do with kids because it's simple and they generally love eating it. If you have a kid you want to fill up, someone who is always hungry or even a kid who doesn't eat enough and needs to - this stuff is great. It's also good to feed unexpected guests. And a great way to use up leftovers.
Our biggest problem is, we often have to cook the potato specially, because we never have enough of it.
I hope this makes sense.
Marg