I agree with rockinrockin. If you make nachos at home with multi grain nachos (one serving, 8 chips, they are large, and 150 calls) and use soem tostitos con queso (40 cals per 2 tbls, not bad at all!, just dip them instead of slathering it on the plate, it will go a lot further!) you can put black beans in taco seasoning on top in place of ground beef, or maybe some lean chicken and veggies, jalapenos, onions, etc. low fat sour cream...
25 cals for 2 tbls.
You could even have one serving for 215 cals (8 chips, two tbls cheese and 2 tbls sour cream, not counting any meat/meat replacement product) That's not bad at all.
One serving with added meat/beans would probably be quite filling and used as sa meal instead of a snack.