In any case, you have a Casseroleof 26 centimeters or larger for such a large party. In terms of capacity, you should easily think about five liters. Depending on what you will be cooking, six liters is a better option. If you are going to cook for six people, you will obviously need a larger pan than for two. On average, you can keep one liter per person.
Besides that it is important that the Casserolelarge enough, you need to make sure that the bottom of your Casseroleis thick enough. Especially for stewing, this is essential. A thick bottom retains heat better and also provides good heat conduction. This is absolutely necessary for a stew. If you really only want to sear a piece of meat briefly, then a Casserolewith a thinner bottom will do just fine.