Drain and press tofu well to get as much liquid out as possible.
Slice the tofu into long flat slices about 1 cm thick and lay them in a shallow dish.
Mix the hot water, oil, nutritional yeast, lemon juice, apple cider vinegar, salt, and garlic powder, and pour it over the tofu. (You can also add a few mint leaves if you are looking for the traditional mint flavor.)
Allow the tofu to marinate for at least 1 hour, but no more than 24 hours or it will start to break down.
Drain the marinade off the tofu. Eat plain or panfry.
Fry or grill the tofu Haloumi
Spread cornstarch out on a plate and press both sides of the tofu into the cornstarch mixture, making sure to coat it completely. Panfry the vegan Halloumi in 1 tablespoon of oil until crispy on the outside.
You can also omit the cornstarch coating and simply pan-fry, use a panini press, or grill the Halloumi tofu for a few minutes on each side.
Serve with tomatoes, mint, or your favorite toppings. Or add it to salads, sandwiches, or wraps.
Notes
If you want spongy Halloumi cheese, place the block of tofu in the freezer for at least 24 hours, then let it thaw in the fridge. This gives the tofu a spongier texture and lets allows it to absorb more liquid and therefore more flavor.
Don't marinate the Halloumi longer than 24 hours or the acid in the lemon juice and apple cider vinegar will start to break down the protein in the tofu and make it too soft.