S.R.
the REALLY simple recipe for the velveeta queso is on the velveeta box. 16 oz velveeta, 10.5 oz can of rotel, melt it together, and viola! Queso! and it definitely will work in a crock pot. for 35 people, i would maybe say to double the recipe. if you use the "mild" rotel, it will have a little bit of bite to it without being too spicy.