Mix together flours, baking powder and salt. Stir in oil and hot water until well mixed.
Knead 2-3 minutes.
Divide and shape into 12 small, smooth balls.
If the dough is a little sticky, roll each little ball around in some flour.
Roll out the balls in the same order that they were shaped, rolling them to 6-7″ in diameter.
Turn the burner on to medium-high and let the skillet get hot before you start to cook the tortillas. (A cast-iron griddle is ideal for this.) Place a rolled-out tortilla on the hot griddle and cook 1 to 2 minutes on each side, or until bubbles appear.
Fold a kitchen towel in half and place the hot tortillas in it.
When they have completely cooled, remove the tortillas from the towel and package them for the freezer. Freeze them unless you plan to use them right away.