With a mortar and pestle of the back of a large heavy spoon mash the garlic, salt and pepper together to a smooth paste. Lightly spread the pork slices with the paste, place them in a bowl and toss with a spoon. Cover tightly and marinate in the refrigerator for 6 hours, turning the pork about in the bowl from time to time.
In a heavy 10-12-inch skillet, melt the lard (or heat olive oil) over high heat. Brown the pok in the hot fat (in 2-3 batches if necessary), turning the slices with tongs and regulating the heat so taht the slices colour quickly and evenly on both sides without burning. As they brown, transfer them to a plate.
Add the sweet red peppers to the fat remaining in the pan and, stirring frequently, cook them for about 5 minutes, or until they are well coated with the fat but not brown. Transfer the pepper to the plate with the meat.
Pour off all but a thing film of fat from the skillet and add the wine and stock. Bring to a boil over high heat, scrapping from the pan any brown particles.
Return pork and sweet peppers to the skillet, cover tightly, and reduce the heat to low. Simmer for about 20-25 minutes, or until pork is tender and shown no resistence when pierced with a small sharp knife.
With a slotted spoon, transfer pork and peppers to a deep heated platter. Bring remaining liquid to a boil over high heat, stirring constantely until lightly thickened.
Taste for seasoning, then pour sauce over the meat. Serve garnished with lemon wedges.