In flat dish, mix together flour, salt and pepper; set aside. Peel avocados and cut into thin slices. Sprinkle with 1/4 cup lemon juice; set aside. Thoroughly dry liver slices. Dip slices of liver and avocado into seasoned flour and pat between hands to give them a thin dusting. Heat 4 Tbsp butter in heavy skillet until foam subsides. Saute liver and avocados quickly, a few at a time, about 1 1/2 minutes per side or until liver is still pink in center. Arrange liver and avocados alternately on heated platter; keep warm. In same skillet, melt 1/2 cup butter. Heat until butter just browns. Add juice of 3 lemons, beef broth, thyme, parsley and wine. Stir to mix. When sauce is bubbling, pour over liver and avocados and serve. Creme de Colorado Cookbook (1987) From the collection of Jim Vorheis