"Champiñones al ajillo", Mushrooms with garlic, is a great Spanish dish. It's really easy: You need champinion mushrooms, a cooked potato with skin, three or four cloves of garlic, two dried chilies, fresh or dried parsley and an enormous amount of olive oil. If you want you can also use bits of cooked chicken, shrimp and other stuff.
Clean the mushrooms, and cut the potato into bite-sized pieces. Slice the garlic cloves lengthwise and remove the center stalk. Remove the chili seeds (or not, if you want it a bit hot). Put all ingredients in a small pan or (as here) in an earthenware pot. Everything should barely fit in the bottom. Pour in enough olive oil to almost cover — that is a lot of olive oil, believe me. Don't panic.
Put the pot on a burner and let everything cook for, oh, fifteen minutes or so. Add plenty of salt and pepper towards the end and finish with parsley. Bring the pot to the table and eat as a main or side dish, with white bread to soak up the oil.
Now, there's a lot more oil than you really want to eat at once, so save the leftover oil in the fridge. It's full of flavour and makes a good base for a pasta sauce. It'll keep for days at least, probably longer, so no need to hurry.
My current favourite pasta with this oil (sorry, no picture) is simple: Cook some spaghetti. Soak a bunch of dried tomatoes in hot water for a while, and cut into largish pieces if needed. Take a boiled potato (yes, I like the potato-oil combination) and cut into pieces. Heat the oil in a skillet, add the tomato and potato and cook them until they just start to change colour a little. The oil is flavoured already so no need to add anything else. Once the pasta is almost done, mix it in with a little of the cooking water and let it cook in the sauce for a little while. Salt and pepper to taste.
Two delicious dinners in one, with minimal effort and great results.