To make tortillas, combine blue corn flour and salt in a bowl. Stir to combine.

Add 1 cup warm water and mix to combine.

Add the all purpose flour and knead for a few minutes until the flour is well incorporated and the dough is a uniform color. Cover with a damp towel and leave to rest for 30 minutes.

Divide dough into 7 equal portions.

Heat a skillet and brush with a little oil.

On a well floured board, roll out to about 5-6" in diameter.

Place on a heated skillet and cook for a few minutes on each side, until there are a few brown spots. Repeat until all the dough has been used.

Now let's make the chayote filling.

Heat oil. Add garlic and scallions and saute for a minute or two, until vegetables are softened.

Add chayote and tomatoes and cook for 5 minutes.

Add chipotles and cook for another 10 minutes, stirring often. Add salt, to taste.

To assemble the tacos, place a little of the chayote filling inside a tortilla. Sprinkle some lettuce and cheese on top. Sprinkle a little cilantro on top. Squeeze a little lime juice on top.