I've been reading Michael Ruhlman's book on 'Ratios' as the basis for understanding the relationships which underpin a whole range of cooking techniques - essentially, the ratios between flour, liquid and fat which every cook needs to remember in order to produce batters, pastries, biscuits, bread, etc. The subject is valid, as anybody will know who has enough experience in the kitchen to have moved beyond the oh-god-which page-was-it-again stage of going back to consult the recipe every three minutes. In fact, though, what the book should really be called IMHO is 'Mnemonics' rather than 'Ratios', firstly, because that's really what the author is talking about, and secondly...well, because his preferred ratios don't agree with mine. His ratio for bread, for instance is five parts flour to three parts liquid, whilst mine is three parts flour to two parts liquid (and to be fair to the man, I did try his method, and then did mine as a direct comparison....and mine was better); his ratio for pastry is three parts flour to two parts fat to 1 part water....where mine is five parts flour to four parts fat, and as little water as you can get away with. I suppose what all this is really saying is that there isn't a one-size-fits-all answer, and that every cook, through trial and error, will find for themselves the techniques (and ingredients) which work best for them, and if you can then make out of your preferred approach some handy numerical mnemonic, then all the better (Ruhlman quotes as a ratio of flour to fat to liquid for making biscuits 'the area code for dialling Chicago'...which is apparently 312; not a particularly useful reference, though, if you live in Chipping Camden, Limoges, or Ulan Bator...)
Having said all of which, Mr Ruhlman does include in his book a recipe for Gnocchi alla Romana, which is entirely reliable, and completely delicious, and which I've reproduced below. I'm not entirely sure what ratio he had in mind when he included this particular recipe, but it has lots of '2's and '4's in it...so it must be some kind of binary system he has in mind. The gnocchi can be served with any sauce you like (pretty much any sauce you would serve with pasta will work) , but I think it goes particularly well with this sauce of fresh tomato, garlic and basil.
For two starter servings.
Ingredients: 2 cups Milk; 2 oz Butter (plus another oz for the sauce); 2 teaspoons Salt; 4 oz Semolina (aka Semola, in Italy); half a dozen grinds of pepper; quarter teaspoon of Nutmeg; half a cup of grated Parmesan (plus some extra, for topping the gnocchi); 2 Egg Yolks; 2 large Tomatoes; 1 clove Garlic; half a dozen large Basil leaves.
1. Put the Milk, Butter, and Salt in a saucepan and place over medium heat until the Butter has completely melted.
2. Add the Semolina to the pan, and, still over medium heat, stir it vigorously until the Semolina has absorbed all of the liquid and can be seen to come cleanly away from the side of the pan as you stir. (For anybody familiar with making Choux Pastry, this process will be immediately recognisable).
3. Off the heat, beat in the Pepper and Nutmeg, and then the Parmesan and the Egg yolks, one by one.
4. Once the mixture is cool enough to handle, spread it in a layer about a third of an inch thick on a greased baking tray, or on a silpat or silicone mat placed on top of a baking tray. Refrigerate until twenty minutes or so before serving.
5. Heat the oven to 220 degrees C, fifteen minutes before dinner.
6. In a small pan, melt the extra oz of Butter, and lightly sauté the minced Garlic; chop the tomatoes, and add these to the pan. Cook over medium heat for ten minutes or so, until the tomatoes have collapsed into their cooking liquid.
7. Using a pastry cutter approx one and a half inches in diameter, cut out the gnocchi from the layer of cooked Semolina, and place these back on the baking tray; sprinkle grated Parmesan over the top, and place in the pre-heated oven for the five minutes or so it takes to heat them through.
8. Add Salt as desired to the Tomato sauce, along with the Basil, finely chopped. Serve in pasta bowls, with half of the sauce underneath the gnocchi, and the remainder on top.