Heat bacon drippings in a large frypan over medium-high heat. Brown roast on all sides. Remove roast to a casserole dish. Place butter, garlic and carrots in the frypan. Reduce heat to medium. Stir in parsley, bay leaf, salt, pepper, tomato paste and sugar. Pour in red wine and stir to combine. Pour over pork roast.
Bake in preheated oven for 1 hour. Remove and arrange mushrooms around the roast. Return to oven, and bake 1/2 hour.