Pop a splash oil to a frying pan, bring to a medium-high heat and chuck in the sliced tofu. Fry until golden brown.
Add in sliced onions and spices, stir well.
Pop in the peppers and mushrooms, cook for a few minutes. Add in the tofu from earlier.
Build the quesadilla with some of the tofu mix on one half, and then top with vegan cheese.
Fold the corn tortilla over the mix and then flip, make sure that both sides are golden.