How to make
Remove the pork loins from the fridge and rub them with half of the rosemary and some black pepper. Leave them at room temperature while you prepare the garnish for the meat.
Peel and cut the onions and apples into very thin crescents. Heat half of the olive oil and all the butter over a moderate heat and fry the onion first, until it softens, then add the apples (it's best to choose a sour green or yellow variety, because the red ones are somewhat fleshier and would break easily).
After a minute, add the sugar and balsamic vinegar and caramelize briefly. When bubbles begin to appear, pour the wine and cognac and stir occasionally, until they evaporate. Sprinkle the remaining rosemary and as much salt as you like. You can adjust the flavor to your liking. If the apples are still crunchy after the liquid has evaporated, add a little water, until they soften and aquire a light caramel color.
Prepare the meat, which has already reached room temperature. Leave the oven heat up to 390°F (200°C). Heat the remaining olive oil over a high heat and sear the tenderloin on all sides, until they aquire a golden color - about a minute on each side. Transfer them into a baking pan and cover them with the fat from the cooking, if there is not much left, add a little more olive oil. Cover with aluminum foil. If your baking pan has a metal handle, putting it directly into the oven is the most convenient option.
Bake for 15 to 20 minutes depending on how you prefer the meat - slightly pink on the inside or fully cooked. A lot depends on the thickness of the loin. Keep in mind that if you overbake it will become dry, so after 14-15 minutes cut it slightly to check it. If you are preparing this dish for the first time, check it if you want to be sure of the result.
After removing it from the oven, leave it for 4-5 minutes without removing the foil.
After this time has passed, cut the tenderloin into thick pieces and season with coarse flaky salt. Garnish with the delicious apples and onions and enjoy this divine combination! If desired, you can pour the sauce from the baking pan, which is incredibly tasty.
Enjoy your meal!
