For those who aren't familiar with butter kuchens yes, the filling is suppose to be runny. That's what makes it gooood. There are other butter kuchens out there that have firmer fillings but this is a spoon kuchen or a sopping kuchen. You're suppose to cut a piece of it and then dip it in the goo that's in the bottom of the pan. If you want a firmer filling then simply add another egg to the filling and omit the water. I think it makes it taste too eggy though when you do that.