Wash the meat under cold water until it whitens. Dry with paper towels. With a very sharp, thin and long knife, cut off the unneeded fat, even though there's barely any in pork loins. Wash the carrots and cut them into long rectangles, cut the garlic into slices and the pepper - into long and narrow strips.
With a knife, make incisions in the pork loins and place a piece of carrot, black pepper grain into each. Make another set of incisions, this time with garlic and black pepper grains only, then another with peppers, alternating on all sides of the loins until out of products. Place any leftovers in the tray in which you'll be baking the meat.
Season the spiked pork loins with salt and black pepper. Pour a little olive oil in a small bowl, add the thyme, pepperoncino, mustard and smear it on thick with a brush all over the meat. Leave it for several hours in the fridge or overnight to take in the aromas.
After the time has elapsed, bake in a pot with olive oil and butter until it gains a brown crisp on all sides. Deglaze the sauce with 2/5 cup (100 ml) quality red wine. Put the braised meat in a suitable container, pour on the sauce and bake at 347°F (175 °C) for about 1 1/2 hours. Let it cool and then cut with a sharp flat knife into slices.
The garnish consists of boiled potatoes crushed with a masher and butter and nutmeg added for flavor. Stir for a decent amount of time with the potato masher so that it takes in air and becomes fluffy. I never use milk when making mashed potatoes.
Source: Mom's recipes.
Notes: I used a quality Cabernet Sauvignon red wine. In one of the photos I've shown what container I used for baking the spiked loins. If you don't have a similar one, you can easily use a deep glass cook pot.