How much filling is the right amount for a taco?

For a double corn tortilla taco: 60-80g of filling total. That is less than most people expect. The restraint is what makes a great taco — each component should be discernible in every bite, which is impossible if you pile everything in. Visually: the filling should sit slightly above the tortilla edge but not overhanging. If anything is hanging over the side you have too much.

The best taquerias use less filling than you think. Part of the discipline is that each individual component has to be made well because there is less of everything. A street taco at a good taqueria is remarkable not because of the quantity but because the small amount of filling is perfectly seasoned and correctly cooked.