Melt the lard in a frying pan and fry the sliced onions and the pork, cut in small pieces. Add the small marrows, cut in chunks, the peeled tomatoes, and lastly, the pimientos, previously sauté in hot fat and cut in strips. Mix all well and moisten with the gravy or stock. Season with salt and pepper and simmer till the stock has been absorbed. Serve with either stuffed or scrambled eggs.