In a bowl, stir together flour, baking powder and salt. Add vegetable oil to the lukewarm milk and whisk briefly to incorporate. Gradually, add the milk to the flour mixture, and using clean hands, work into a sticky dough.
Turn dough out onto a surface dusted with flour and knead vigorously for about 2 minutes or until the dough is no longer sticky.
Return dough to bowl, cover with a damp cloth and allow rest to 10-20 minutes so that it will be easier to roll out.
Divide dough into 8 balls of equal size, cover them, and let them rest again for about 20 minutes. Avoid letting them touch, if you don't want them to stick together.
Dust a clean pastry board or working surface with flour.
One at a time, remove each piece of dough. Press it out into a 6 inch circle. Using a flour dusted rolling pin, roll out the tortilla from the center out until the tortilla measures as little less than 1/4 inch thick and is a 7-8 inch circle.
Transfer the tortilla to a dry preheated cast iron griddle or skillet. When the tortilla begins to blister, allow it to cook for 30 seconds (don't let it burn), flip it and cook the other side the same way.