Pork with tenders

6 tablespoons vegetable oil, divided (plus more if needed) 1 1/2 cups chopped onions 1 cup diced carrot (1/2-inch dice) 2 tablespoons minced serrano peppers 3[...]

3 lbs pork tenderloin, whole 1 1/2 teaspoons salt 3/4 teaspoon fresh ground black pepper 2 tablespoons vegetable oil 2 cloves garlic , minced 2 tablespoons[...]