How to Make It
Preheat oven to 350°. Unroll lamb, if necessary. Rub 1 lemon half on all sides of lamb, squeezing juice from lemon. Stir together oregano, salt, and pepper; rub on lamb. Roll up lamb, and tie with kitchen string.
Place lamb on a lightly greased rack in a roasting pan. Separate garlic cloves (do not peel), and place around roast. Drizzle olive oil over lamb and garlic cloves.
Squeeze juice from remaining 1 1/2 lemons into a bowl. Stir together juice and chicken broth; pour into roasting pan.
Bake at 350° for 2 hours to 2 hours and 15 minutes or until a meat thermometer inserted into thickest portion registers 140° (medium) or to desired degree of doneness. Remove lamb from pan; cover with aluminum foil, and let stand 10 minutes before slicing. Garnish, if desired.