Just order more! If you're concerned about price, go on Taco Tuesdays when it's 39NT a taco (excluding fish tacos). Not sure how you can give a restaurant a bad review just because they didn't give you enough food. Not like they purposely have a rule where men above 6ft aren't served standard portions. They most likely have an SOP for portions and follow it. However, the restaurant lashing back out at your review is not the best business decision.
You guys can try Twinkeyz Tacos near SYS Memorial Hall. If you're familiar with the area, it's on the same side street as Little London. I find their tacos pretty good, but just expensive at 60-70NT a taco.
Nala's Mexican Food I hear is not too bad and is located right next to Revolver.
If eating out fails, Costco's huge portions of ground beef would probably satisfy your request for bigger portions. If you don't have a recipe, ask nicely and maybe hermana @Icon will share her's with you.
For other options, try the Taiwanese steak places where they serve you egg, noodles and steak on a hot plate. You can consider buffets too.