Where can I find a list of recipes (and their directions) that were used in Shokugeki no Soma? I'm reading Shokugeki no Soma and at some points, I thought it would be nice to cook some of these dishes. Unfortunately, I haven't found more than the mackerel burger recipe. I know that not all recipes are published, but I would like to know if there were also other ones that were published.
As Krazer said, the recipes can be found on the Japanese tankobon versions as extras. The English version, however, also have the same recipes. At the time of this writing, 6 volumes have been released in English and this Imgur album contains the English version of the recipes up to the 6th volume. It doesn't contain all of the recipes, as you guessed yourself, but it contains most of the meals that the main cast cooked. 

You can also find partial recipes in the Shokugeki no Soma wiki by looking up the names of the food. They usually only contain the ingredients and not step-by-step instructions on how to prepare the food.