Mix the two flours, salt and baking powder together in a mixing bowl. Sift if necessary., i.e. if you find any lumps in the flour or baking powder. Ensure there aren't any lumps in baking powder though.
Add the oil to the flour and mix it swiftly with a spoon. After that, using the tips of your fingers, rub the oil into the flour until it resembles sand.
Heat the water until it starts bubbling on the sides and pour it into the flour mixture. Mix it with a spatula and once it is cool enough to handle, start kneading the dough until it forms a smooth dough.
Transfer it to the counter and knead it for 5 minutes. Rest for 5 minutes and knead for 5 more minutes.
Divide the ball of dough into 8 equal portions for medium tortillas or 6 equal portions for large tortillas. I'm gonna go with 8 portions here.
Make individual balls from each portion and gently press it on the counter to make discs. Put them on a baking tray and cover it with a moist cloth. Let it rest for 45 minutes.
After the resting time, roll out each disc into a circular shape, approximately 8 inch in diameter. The edges and the shape may not be perfect, you can use a side plate to trim it into perfect circular shape.
Heat a 10 inch skillet and once it is hot enough, place the rolled out dough on the skillet. Cook for 2 minutes on each side on medium flame or until you can see brown spots on each side. Transfer it to a plate and cover with a clean dry cloth.
Reduce the heat to a minimum, and roll out the next disc and cook it. Repeat the same with all the other discs.