I have made this recipe several times. Once you have the basics on hand the dish goes together in no time at all. When I asked my sister in law, who is Japanese, where to get some of the more esoteric ingredients, she said "Japan". She did give some of her personal stash of ingredients her mother sends over to her but I have made awesome Ramen using stuff I sourced locally. Orkin isn't kidding when he says to play around with the dish. It is very forgiving of almost any kind of tinkering. One thing I did want to clear up is about the Sofrito. The oil should be drained and discarded/reserved for something else. In this recipe here: http://www.foodandwine.com/recipes/chile-eggplant-mazemen-ramen-with-pork-belly Orkin says to drain the oil in step 2. MEANWHILE, MAKE THE SOFRITO In a large saucepan, heat the oil. Add the onion and eggplant and cook over low heat, stirring occasionally, until the vegetables are very soft, about 1 hour. Add the tomatoes and cook, stirring occasionally, until the tomatoes have almost melted, about 1 hour. Stir in the chipotle powder and cook for 15 minutes longer; season with salt. Transfer the sofrito to a bowl and let cool to room temperature. Drain the sofrito in a sieve; discard the oil or reserve it for another use. I initially used the oily version and it was a mess.
I think J is right. When I made the dish with the drained sofrito I found I was adding a little more pork and duck (I know the recipe calls for shmaltz but I had duck fat on hand and I quite like it with that) fat to keep it the right consistency. The recipe in the book version I have says it makes 2 1/2 cups but calls for a litre (4 cups) of oil, a clear contradiction. The next time I make the sofrito I am going to use just enough oil to 'encapsulate' the ingredients so that when it is stored in a jar there is no extra oil floating on top. I think it really comes down to personal preference and judgement. As Ivan says, make it your own.