Trim excess fat from fresh beef brisket, reserving some of the trimmings.
In large skillet heat reserved trimmings till about 2 tablespoons fat accumulate; discard trimmings.
Brown meat on both sides in hot fat.
Transfer meat to a 12x7 1/2x2-inch baking dish.
Add onion, celery, carrot, green pepper, water, cloves, allspice, garlic (speared onto wooden pick), bay leaf, and paprika.
Sprinkle with salt and pepper.
Cover tightly with foil.
Bake at 325° till meat is tender, about 3 hours.
Meanwhile, in medium saucepan heat flour over medium-high heat, stirring constantly, till flour turns a dark beige color, 10 to 15 minutes.
Cool; reserve for gravy.
Transfer meat to serving platter.
Remove cloves, allspice, garlic, and bay leaf.
Drain vegetables, reserving cooking juices.
Spoon vegetables over meat; keep warm.
In saucepan blend 3/4 cup of the beef broth with browned flour.
Pour reserved cooking juices into measuring cup; add remaining beef broth, plus water if necessary, to make 1 1/2 cups liquid.
Stir into flour mixture.
Cook and stir till thickened and bubbly; cook and stir 2 minutes more.
Serve gravy with meat and vegetables.