Melt butter with oil in large soup pot - add sliced onions and stir to coat ~ cover pot and cook over moderately low heat for 15 - 20 minutes - stirring occasionally until onions are tender and translucent. Uncover pot and raise heat to moderately high - stir in salt and sugar (sugar carmelizes and helps onions to brown) - cook about 30 minutes - stirring frequently until onions have turned an even deep golden brown. Lower heat to moderate - stir in flour and add a bit more butter if flour does not absorb into a paste with the onions. Cook slowly, stirring constantly for 12 minutes to brown flour lightly. Remove from heat - pour about 1 cup of warmed consomme into onion/flour mixture to blend flour and consomme - add rest of consomme, water, wine, bay leaf and sage - bring to a simmer. Simmer slowly for 30 - 40 minutes. If you are not serving right away, let cool, uncovered, then cover and refrigerate. Reheat when ready to serve - place in ovenproof soup bowls - top with a slice of toasted french bread, shredded mozzarella cheese and parmesan cheese. Place under broiler to melt cheeses until bubbly. Posted to MM-Recipes Digest V5 #021 by lena36@juno.com (Lena P Mitchell) on Jan 20, 1998